C++中生成随机数的方法总结

#include<stdlib.h> 
#include<time.h> 

srand(time(nullptr));//设置随机数种子
rand();//产生一个随机数

{//产生 [0,b) 范围内到随机数  
  int randoxNumber = rand() % b ;
}
{//产生 [a,b) 范围内到随机数 
    int randoxNumber = a + rand() % ( b -a ) ;
}
{//产生 [a,b] 范围内到随机数 
    int randoxNumber = a + rand() % ( b -a +1 ) ;
}
{//产生 [0,1] 范围内到随机小数 
    double randoxNumber =rand() / RAND_MAX
}
{//产生 [0,1) 范围内到随机小数 
    double randoxNumber =rand() / ( RAND_MAX +1 )
}

random_device rd;
for (int i = 0; i < 10; ++i)
{
  cout << rd() << endl;
}

random_device rd;
  
default_random_engine r_eng(rd());
for (int i = 0; i < 10; ++i)
{
  cout << r_eng() << endl;
}

random_device rd;
  
minstd_rand   r_eng(rd());
for (int i = 0; i < 10; ++i)
{
  cout << r_eng() << endl;
}

random_device rd;
  
mt19937  r_eng(rd());
for (int i = 0; i < 10; ++i)
{
  cout << r_eng() << endl;
}

random_device rd;
  
ranlux24_base  r_eng(rd());
for (int i = 0; i < 10; ++i)
{
  cout << r_eng() << endl;
}

random_device rd;//用于生成随机数种子
mt19937 r_eng(rd());//随机数生成器  
uniform_int_distribution<int> dis(1, 100);//随机数分布器 闭区间

for (int i = 0; i < 10; ++i)
{
  cout << dis(r_eng) << endl;
}

random_device rd;//用于生成随机数种子
mt19937 r_eng(rd());//随机数生成器  
uniform_real_distribution<double> dis(1, 100);//随机数分布器 闭区间

for (int i = 0; i < 10; ++i)
{
  cout << dis(r_eng) << endl;
}

random_device rd;//用于生成随机数种子
mt19937 r_eng(rd());//随机数生成器  
normal_distribution  <> dis(4, 1.5);//随机数分布器，均值、方差

for (int i = 0; i < 10; ++i)
{
  cout << dis(r_eng) << endl;
}

random_device rd;//用于生成随机数种子
mt19937 r_eng(rd());//随机数生成器  
bernoulli_distribution   dis( 0.6);//随机数分布器，生成 1 的概率是 0.6

for (int i = 0; i < 10; ++i)
{
  cout << dis(r_eng) << endl;
}

auto seed = QDateTime::currentDateTime().toMSecsSinceEpoch();

qsrand(seed);
for (int i = 0; i < 10; ++i)
{
  qDebug() << qrand() % 10;// 0 - 9 范围
}