random between [a,b]、(a,b]、[a,b)

#include <iostream>

#include <ctime>

#include <cstdlib>

using namespace std;

const int n = 10;

/*cstdlib头文件要和ctime一起，否则无法使用srand*/

void RandBetween(int s, int d, int num)

{

    int result;

    srand((unsigned)time(NULL));

    for(int i=0; i<num; i++)

    {

        result = rand() % (d - s) + s + 1;// (s,d]

        result = rand() % (d - s) + s;// [s,d)

        result = rand() % (d - s + 1) + s;// [s,d]

        cout << result << endl;

    }

}



int main()

{

    int first, second;

    cout << "input start and end: ";

    cin >> first >> second;

    RandBetween(first, second, n);

    return 0;

}