特定范围内的随机数

Question

我想显示随机数特定范围[from, to]。以下代码写出该值，但某些内容无法正常工作：

#include <iostream>
#include <cstdlib>
#include <ctime>

using namespace std;

int draw(int from_to, int to_from)
{
    return (rand()%to_from)+from_to;
}
int main()
{
    srand(time(NULL));
    int start,stop;
    cout << "First number: " << endl;
    cin >> start;
    cout << "Last number: " << endl;
    cin >> stop;
    int x=20;
    do
    {
        cout << draw(start,stop) << endl;
        x--;
    } while(x>0);

    return 0;
}

Answer 1

尝试从指定范围生成随机数的 C++11 功能：

#include <random>
#include <iostream>

int main() {
    int from = 0;
    int to   = 100;

    std::random_device device;
    std::mt19937 generator(device());
    std::uniform_int_distribution<std::mt19937::result_type> distribution(from, to);

    std::cout << distribution(generator) << std::endl;
}

演示