<random>

public member function (公共成员函数)
<random>

std::subtract_with_carry_engine::operator()

result_type operator()();
生成随机数
Returns a new random number. (返回一个新的随机数。)

The function advances the internal state by calling its transition algorithm which applies a subtract-with-carry operation on the state sequence element. (该函数通过调用其 *转换算法* 来推进内部状态,该算法对状态序列元素应用减法进位运算。)

Its generation algorithm is a direct copy of the value generated with the transition algorithm. (它的 *生成算法* 是使用 *转换算法* 生成的值的直接副本。)

参数



返回值

A new random number. (一个新的随机数。)
result_type (结果类型)是一个成员类型,定义为第一个类模板参数的别名 (UIntType).

示例

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// subtract_with_carry::operator()
#include <iostream>
#include <chrono>
#include <random>

int main ()
{
  // obtain a seed from the system clock:
  unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();

  std::subtract_with_carry_engine<unsigned,24,10,24> generator (seed);
  std::cout << "Random value: " << generator() << std::endl;

  return 0;
}

可能的输出
Random value: 2780326


复杂度

Amortized constant. (分摊常数。)

另见