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1 | 13 | up20180614 | // -*- C++ -*- |
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2 | //===---------------------------- ratio -----------------------------------===// |
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3 | // |
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4 | // The LLVM Compiler Infrastructure |
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5 | // |
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6 | // This file is dual licensed under the MIT and the University of Illinois Open |
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7 | // Source Licenses. See LICENSE.TXT for details. |
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8 | // |
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9 | //===----------------------------------------------------------------------===// |
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10 | |||
11 | #ifndef _LIBCPP_RATIO |
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12 | #define _LIBCPP_RATIO |
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13 | |||
14 | /* |
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15 | ratio synopsis |
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16 | |||
17 | namespace std |
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18 | { |
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19 | |||
20 | template <intmax_t N, intmax_t D = 1> |
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21 | class ratio |
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22 | { |
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23 | public: |
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24 | static constexpr intmax_t num; |
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25 | static constexpr intmax_t den; |
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26 | typedef ratio<num, den> type; |
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27 | }; |
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28 | |||
29 | // ratio arithmetic |
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30 | template <class R1, class R2> using ratio_add = ...; |
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31 | template <class R1, class R2> using ratio_subtract = ...; |
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32 | template <class R1, class R2> using ratio_multiply = ...; |
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33 | template <class R1, class R2> using ratio_divide = ...; |
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34 | |||
35 | // ratio comparison |
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36 | template <class R1, class R2> struct ratio_equal; |
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37 | template <class R1, class R2> struct ratio_not_equal; |
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38 | template <class R1, class R2> struct ratio_less; |
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39 | template <class R1, class R2> struct ratio_less_equal; |
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40 | template <class R1, class R2> struct ratio_greater; |
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41 | template <class R1, class R2> struct ratio_greater_equal; |
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42 | |||
43 | // convenience SI typedefs |
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44 | typedef ratio<1, 1000000000000000000000000> yocto; // not supported |
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45 | typedef ratio<1, 1000000000000000000000> zepto; // not supported |
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46 | typedef ratio<1, 1000000000000000000> atto; |
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47 | typedef ratio<1, 1000000000000000> femto; |
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48 | typedef ratio<1, 1000000000000> pico; |
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49 | typedef ratio<1, 1000000000> nano; |
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50 | typedef ratio<1, 1000000> micro; |
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51 | typedef ratio<1, 1000> milli; |
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52 | typedef ratio<1, 100> centi; |
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53 | typedef ratio<1, 10> deci; |
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54 | typedef ratio< 10, 1> deca; |
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55 | typedef ratio< 100, 1> hecto; |
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56 | typedef ratio< 1000, 1> kilo; |
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57 | typedef ratio< 1000000, 1> mega; |
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58 | typedef ratio< 1000000000, 1> giga; |
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59 | typedef ratio< 1000000000000, 1> tera; |
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60 | typedef ratio< 1000000000000000, 1> peta; |
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61 | typedef ratio< 1000000000000000000, 1> exa; |
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62 | typedef ratio< 1000000000000000000000, 1> zetta; // not supported |
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63 | typedef ratio<1000000000000000000000000, 1> yotta; // not supported |
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64 | |||
65 | } |
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66 | */ |
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67 | |||
68 | #include <__config> |
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69 | #include <cstdint> |
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70 | #include <climits> |
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71 | #include <type_traits> |
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72 | |||
73 | #include <__undef_min_max> |
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74 | |||
75 | #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
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76 | #pragma GCC system_header |
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77 | #endif |
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78 | |||
79 | _LIBCPP_BEGIN_NAMESPACE_STD |
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80 | |||
81 | // __static_gcd |
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82 | |||
83 | template <intmax_t _Xp, intmax_t _Yp> |
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84 | struct __static_gcd |
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85 | { |
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86 | static const intmax_t value = __static_gcd<_Yp, _Xp % _Yp>::value; |
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87 | }; |
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88 | |||
89 | template <intmax_t _Xp> |
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90 | struct __static_gcd<_Xp, 0> |
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91 | { |
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92 | static const intmax_t value = _Xp; |
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93 | }; |
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94 | |||
95 | template <> |
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96 | struct __static_gcd<0, 0> |
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97 | { |
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98 | static const intmax_t value = 1; |
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99 | }; |
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100 | |||
101 | // __static_lcm |
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102 | |||
103 | template <intmax_t _Xp, intmax_t _Yp> |
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104 | struct __static_lcm |
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105 | { |
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106 | static const intmax_t value = _Xp / __static_gcd<_Xp, _Yp>::value * _Yp; |
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107 | }; |
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108 | |||
109 | template <intmax_t _Xp> |
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110 | struct __static_abs |
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111 | { |
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112 | static const intmax_t value = _Xp < 0 ? -_Xp : _Xp; |
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113 | }; |
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114 | |||
115 | template <intmax_t _Xp> |
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116 | struct __static_sign |
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117 | { |
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118 | static const intmax_t value = _Xp == 0 ? 0 : (_Xp < 0 ? -1 : 1); |
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119 | }; |
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120 | |||
121 | template <intmax_t _Xp, intmax_t _Yp, intmax_t = __static_sign<_Yp>::value> |
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122 | class __ll_add; |
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123 | |||
124 | template <intmax_t _Xp, intmax_t _Yp> |
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125 | class __ll_add<_Xp, _Yp, 1> |
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126 | { |
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127 | static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1; |
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128 | static const intmax_t max = -min; |
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129 | |||
130 | static_assert(_Xp <= max - _Yp, "overflow in __ll_add"); |
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131 | public: |
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132 | static const intmax_t value = _Xp + _Yp; |
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133 | }; |
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134 | |||
135 | template <intmax_t _Xp, intmax_t _Yp> |
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136 | class __ll_add<_Xp, _Yp, 0> |
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137 | { |
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138 | public: |
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139 | static const intmax_t value = _Xp; |
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140 | }; |
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141 | |||
142 | template <intmax_t _Xp, intmax_t _Yp> |
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143 | class __ll_add<_Xp, _Yp, -1> |
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144 | { |
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145 | static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1; |
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146 | static const intmax_t max = -min; |
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147 | |||
148 | static_assert(min - _Yp <= _Xp, "overflow in __ll_add"); |
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149 | public: |
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150 | static const intmax_t value = _Xp + _Yp; |
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151 | }; |
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152 | |||
153 | template <intmax_t _Xp, intmax_t _Yp, intmax_t = __static_sign<_Yp>::value> |
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154 | class __ll_sub; |
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155 | |||
156 | template <intmax_t _Xp, intmax_t _Yp> |
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157 | class __ll_sub<_Xp, _Yp, 1> |
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158 | { |
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159 | static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1; |
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160 | static const intmax_t max = -min; |
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161 | |||
162 | static_assert(min + _Yp <= _Xp, "overflow in __ll_sub"); |
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163 | public: |
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164 | static const intmax_t value = _Xp - _Yp; |
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165 | }; |
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166 | |||
167 | template <intmax_t _Xp, intmax_t _Yp> |
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168 | class __ll_sub<_Xp, _Yp, 0> |
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169 | { |
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170 | public: |
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171 | static const intmax_t value = _Xp; |
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172 | }; |
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173 | |||
174 | template <intmax_t _Xp, intmax_t _Yp> |
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175 | class __ll_sub<_Xp, _Yp, -1> |
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176 | { |
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177 | static const intmax_t min = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1; |
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178 | static const intmax_t max = -min; |
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179 | |||
180 | static_assert(_Xp <= max + _Yp, "overflow in __ll_sub"); |
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181 | public: |
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182 | static const intmax_t value = _Xp - _Yp; |
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183 | }; |
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184 | |||
185 | template <intmax_t _Xp, intmax_t _Yp> |
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186 | class __ll_mul |
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187 | { |
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188 | static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)); |
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189 | static const intmax_t min = nan + 1; |
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190 | static const intmax_t max = -min; |
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191 | static const intmax_t __a_x = __static_abs<_Xp>::value; |
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192 | static const intmax_t __a_y = __static_abs<_Yp>::value; |
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193 | |||
194 | static_assert(_Xp != nan && _Yp != nan && __a_x <= max / __a_y, "overflow in __ll_mul"); |
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195 | public: |
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196 | static const intmax_t value = _Xp * _Yp; |
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197 | }; |
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198 | |||
199 | template <intmax_t _Yp> |
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200 | class __ll_mul<0, _Yp> |
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201 | { |
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202 | public: |
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203 | static const intmax_t value = 0; |
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204 | }; |
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205 | |||
206 | template <intmax_t _Xp> |
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207 | class __ll_mul<_Xp, 0> |
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208 | { |
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209 | public: |
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210 | static const intmax_t value = 0; |
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211 | }; |
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212 | |||
213 | template <> |
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214 | class __ll_mul<0, 0> |
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215 | { |
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216 | public: |
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217 | static const intmax_t value = 0; |
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218 | }; |
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219 | |||
220 | // Not actually used but left here in case needed in future maintenance |
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221 | template <intmax_t _Xp, intmax_t _Yp> |
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222 | class __ll_div |
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223 | { |
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224 | static const intmax_t nan = (1LL << (sizeof(intmax_t) * CHAR_BIT - 1)); |
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225 | static const intmax_t min = nan + 1; |
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226 | static const intmax_t max = -min; |
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227 | |||
228 | static_assert(_Xp != nan && _Yp != nan && _Yp != 0, "overflow in __ll_div"); |
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229 | public: |
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230 | static const intmax_t value = _Xp / _Yp; |
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231 | }; |
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232 | |||
233 | template <intmax_t _Num, intmax_t _Den = 1> |
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234 | class _LIBCPP_TYPE_VIS_ONLY ratio |
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235 | { |
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236 | static_assert(__static_abs<_Num>::value >= 0, "ratio numerator is out of range"); |
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237 | static_assert(_Den != 0, "ratio divide by 0"); |
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238 | static_assert(__static_abs<_Den>::value > 0, "ratio denominator is out of range"); |
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239 | static _LIBCPP_CONSTEXPR const intmax_t __na = __static_abs<_Num>::value; |
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240 | static _LIBCPP_CONSTEXPR const intmax_t __da = __static_abs<_Den>::value; |
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241 | static _LIBCPP_CONSTEXPR const intmax_t __s = __static_sign<_Num>::value * __static_sign<_Den>::value; |
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242 | static _LIBCPP_CONSTEXPR const intmax_t __gcd = __static_gcd<__na, __da>::value; |
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243 | public: |
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244 | static _LIBCPP_CONSTEXPR const intmax_t num = __s * __na / __gcd; |
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245 | static _LIBCPP_CONSTEXPR const intmax_t den = __da / __gcd; |
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246 | |||
247 | typedef ratio<num, den> type; |
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248 | }; |
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249 | |||
250 | template <intmax_t _Num, intmax_t _Den> |
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251 | _LIBCPP_CONSTEXPR const intmax_t ratio<_Num, _Den>::num; |
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252 | |||
253 | template <intmax_t _Num, intmax_t _Den> |
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254 | _LIBCPP_CONSTEXPR const intmax_t ratio<_Num, _Den>::den; |
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255 | |||
256 | template <class _Tp> struct __is_ratio : false_type {}; |
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257 | template <intmax_t _Num, intmax_t _Den> struct __is_ratio<ratio<_Num, _Den> > : true_type {}; |
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258 | |||
259 | typedef ratio<1LL, 1000000000000000000LL> atto; |
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260 | typedef ratio<1LL, 1000000000000000LL> femto; |
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261 | typedef ratio<1LL, 1000000000000LL> pico; |
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262 | typedef ratio<1LL, 1000000000LL> nano; |
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263 | typedef ratio<1LL, 1000000LL> micro; |
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264 | typedef ratio<1LL, 1000LL> milli; |
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265 | typedef ratio<1LL, 100LL> centi; |
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266 | typedef ratio<1LL, 10LL> deci; |
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267 | typedef ratio< 10LL, 1LL> deca; |
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268 | typedef ratio< 100LL, 1LL> hecto; |
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269 | typedef ratio< 1000LL, 1LL> kilo; |
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270 | typedef ratio< 1000000LL, 1LL> mega; |
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271 | typedef ratio< 1000000000LL, 1LL> giga; |
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272 | typedef ratio< 1000000000000LL, 1LL> tera; |
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273 | typedef ratio< 1000000000000000LL, 1LL> peta; |
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274 | typedef ratio<1000000000000000000LL, 1LL> exa; |
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275 | |||
276 | template <class _R1, class _R2> |
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277 | struct __ratio_multiply |
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278 | { |
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279 | private: |
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280 | static const intmax_t __gcd_n1_d2 = __static_gcd<_R1::num, _R2::den>::value; |
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281 | static const intmax_t __gcd_d1_n2 = __static_gcd<_R1::den, _R2::num>::value; |
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282 | public: |
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283 | typedef typename ratio |
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284 | < |
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285 | __ll_mul<_R1::num / __gcd_n1_d2, _R2::num / __gcd_d1_n2>::value, |
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286 | __ll_mul<_R2::den / __gcd_n1_d2, _R1::den / __gcd_d1_n2>::value |
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287 | >::type type; |
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288 | }; |
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289 | |||
290 | #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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291 | |||
292 | template <class _R1, class _R2> using ratio_multiply |
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293 | = typename __ratio_multiply<_R1, _R2>::type; |
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294 | |||
295 | #else // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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296 | |||
297 | template <class _R1, class _R2> |
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298 | struct _LIBCPP_TYPE_VIS_ONLY ratio_multiply |
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299 | : public __ratio_multiply<_R1, _R2>::type {}; |
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300 | |||
301 | #endif // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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302 | |||
303 | template <class _R1, class _R2> |
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304 | struct __ratio_divide |
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305 | { |
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306 | private: |
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307 | static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value; |
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308 | static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value; |
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309 | public: |
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310 | typedef typename ratio |
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311 | < |
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312 | __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value, |
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313 | __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value |
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314 | >::type type; |
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315 | }; |
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316 | |||
317 | #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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318 | |||
319 | template <class _R1, class _R2> using ratio_divide |
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320 | = typename __ratio_divide<_R1, _R2>::type; |
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321 | |||
322 | #else // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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323 | |||
324 | template <class _R1, class _R2> |
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325 | struct _LIBCPP_TYPE_VIS_ONLY ratio_divide |
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326 | : public __ratio_divide<_R1, _R2>::type {}; |
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327 | |||
328 | #endif // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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329 | |||
330 | template <class _R1, class _R2> |
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331 | struct __ratio_add |
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332 | { |
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333 | private: |
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334 | static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value; |
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335 | static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value; |
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336 | public: |
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337 | typedef typename ratio_multiply |
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338 | < |
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339 | ratio<__gcd_n1_n2, _R1::den / __gcd_d1_d2>, |
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340 | ratio |
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341 | < |
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342 | __ll_add |
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343 | < |
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344 | __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value, |
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345 | __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value |
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346 | >::value, |
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347 | _R2::den |
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348 | > |
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349 | >::type type; |
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350 | }; |
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351 | |||
352 | #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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353 | |||
354 | template <class _R1, class _R2> using ratio_add |
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355 | = typename __ratio_add<_R1, _R2>::type; |
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356 | |||
357 | #else // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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358 | |||
359 | template <class _R1, class _R2> |
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360 | struct _LIBCPP_TYPE_VIS_ONLY ratio_add |
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361 | : public __ratio_add<_R1, _R2>::type {}; |
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362 | |||
363 | #endif // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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364 | |||
365 | template <class _R1, class _R2> |
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366 | struct __ratio_subtract |
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367 | { |
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368 | private: |
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369 | static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value; |
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370 | static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value; |
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371 | public: |
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372 | typedef typename ratio_multiply |
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373 | < |
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374 | ratio<__gcd_n1_n2, _R1::den / __gcd_d1_d2>, |
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375 | ratio |
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376 | < |
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377 | __ll_sub |
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378 | < |
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379 | __ll_mul<_R1::num / __gcd_n1_n2, _R2::den / __gcd_d1_d2>::value, |
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380 | __ll_mul<_R2::num / __gcd_n1_n2, _R1::den / __gcd_d1_d2>::value |
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381 | >::value, |
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382 | _R2::den |
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383 | > |
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384 | >::type type; |
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385 | }; |
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386 | |||
387 | #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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388 | |||
389 | template <class _R1, class _R2> using ratio_subtract |
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390 | = typename __ratio_subtract<_R1, _R2>::type; |
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391 | |||
392 | #else // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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393 | |||
394 | template <class _R1, class _R2> |
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395 | struct _LIBCPP_TYPE_VIS_ONLY ratio_subtract |
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396 | : public __ratio_subtract<_R1, _R2>::type {}; |
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397 | |||
398 | #endif // _LIBCPP_HAS_NO_TEMPLATE_ALIASES |
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399 | |||
400 | // ratio_equal |
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401 | |||
402 | template <class _R1, class _R2> |
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403 | struct _LIBCPP_TYPE_VIS_ONLY ratio_equal |
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404 | : public _LIBCPP_BOOL_CONSTANT((_R1::num == _R2::num && _R1::den == _R2::den)) {}; |
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405 | |||
406 | template <class _R1, class _R2> |
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407 | struct _LIBCPP_TYPE_VIS_ONLY ratio_not_equal |
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408 | : public _LIBCPP_BOOL_CONSTANT((!ratio_equal<_R1, _R2>::value)) {}; |
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409 | |||
410 | // ratio_less |
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411 | |||
412 | template <class _R1, class _R2, bool _Odd = false, |
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413 | intmax_t _Q1 = _R1::num / _R1::den, intmax_t _M1 = _R1::num % _R1::den, |
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414 | intmax_t _Q2 = _R2::num / _R2::den, intmax_t _M2 = _R2::num % _R2::den> |
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415 | struct __ratio_less1 |
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416 | { |
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417 | static const bool value = _Odd ? _Q2 < _Q1 : _Q1 < _Q2; |
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418 | }; |
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419 | |||
420 | template <class _R1, class _R2, bool _Odd, intmax_t _Qp> |
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421 | struct __ratio_less1<_R1, _R2, _Odd, _Qp, 0, _Qp, 0> |
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422 | { |
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423 | static const bool value = false; |
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424 | }; |
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425 | |||
426 | template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M2> |
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427 | struct __ratio_less1<_R1, _R2, _Odd, _Qp, 0, _Qp, _M2> |
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428 | { |
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429 | static const bool value = !_Odd; |
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430 | }; |
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431 | |||
432 | template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M1> |
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433 | struct __ratio_less1<_R1, _R2, _Odd, _Qp, _M1, _Qp, 0> |
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434 | { |
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435 | static const bool value = _Odd; |
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436 | }; |
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437 | |||
438 | template <class _R1, class _R2, bool _Odd, intmax_t _Qp, intmax_t _M1, |
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439 | intmax_t _M2> |
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440 | struct __ratio_less1<_R1, _R2, _Odd, _Qp, _M1, _Qp, _M2> |
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441 | { |
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442 | static const bool value = __ratio_less1<ratio<_R1::den, _M1>, |
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443 | ratio<_R2::den, _M2>, !_Odd>::value; |
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444 | }; |
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445 | |||
446 | template <class _R1, class _R2, intmax_t _S1 = __static_sign<_R1::num>::value, |
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447 | intmax_t _S2 = __static_sign<_R2::num>::value> |
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448 | struct __ratio_less |
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449 | { |
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450 | static const bool value = _S1 < _S2; |
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451 | }; |
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452 | |||
453 | template <class _R1, class _R2> |
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454 | struct __ratio_less<_R1, _R2, 1LL, 1LL> |
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455 | { |
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456 | static const bool value = __ratio_less1<_R1, _R2>::value; |
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457 | }; |
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458 | |||
459 | template <class _R1, class _R2> |
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460 | struct __ratio_less<_R1, _R2, -1LL, -1LL> |
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461 | { |
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462 | static const bool value = __ratio_less1<ratio<-_R2::num, _R2::den>, ratio<-_R1::num, _R1::den> >::value; |
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463 | }; |
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464 | |||
465 | template <class _R1, class _R2> |
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466 | struct _LIBCPP_TYPE_VIS_ONLY ratio_less |
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467 | : public _LIBCPP_BOOL_CONSTANT((__ratio_less<_R1, _R2>::value)) {}; |
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468 | |||
469 | template <class _R1, class _R2> |
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470 | struct _LIBCPP_TYPE_VIS_ONLY ratio_less_equal |
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471 | : public _LIBCPP_BOOL_CONSTANT((!ratio_less<_R2, _R1>::value)) {}; |
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472 | |||
473 | template <class _R1, class _R2> |
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474 | struct _LIBCPP_TYPE_VIS_ONLY ratio_greater |
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475 | : public _LIBCPP_BOOL_CONSTANT((ratio_less<_R2, _R1>::value)) {}; |
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476 | |||
477 | template <class _R1, class _R2> |
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478 | struct _LIBCPP_TYPE_VIS_ONLY ratio_greater_equal |
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479 | : public _LIBCPP_BOOL_CONSTANT((!ratio_less<_R1, _R2>::value)) {}; |
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480 | |||
481 | template <class _R1, class _R2> |
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482 | struct __ratio_gcd |
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483 | { |
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484 | typedef ratio<__static_gcd<_R1::num, _R2::num>::value, |
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485 | __static_lcm<_R1::den, _R2::den>::value> type; |
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486 | }; |
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487 | |||
488 | _LIBCPP_END_NAMESPACE_STD |
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489 | |||
490 | #endif // _LIBCPP_RATIO |