cpp rand

1std::srand(std::time(nullptr)); 		// set rand seed
2v1 = std::rand() % 100;         // v1 in the range 0 to 99
3v2 = std::rand() % 100 + 1;     // v2 in the range 1 to 100
4v3 = std::rand() % 30 + 1985;   // v3 in the range 1985-2014 

1#include <cstdlib>
2#include <iostream>
3#include <ctime>
4 
5int main() 
6{
7    std::srand(std::time(nullptr)); // use current time as seed for random generator
8    int random_variable = std::rand();
9    std::cout << "Random value on [0 " << RAND_MAX << "]: " 
10              << random_variable << '\n';
11}

1#include <cstdlib>
2#include <iostream>
3#include <ctime>
4 
5int main() 
6{
7    std::srand(std::time(nullptr)); // use current time as seed for random generator
8    int random_variable = std::rand();
9    std::cout << "Random value on [0 " << RAND_MAX << "]: " 
10              << random_variable << '\n';
11 
12    // roll 6-sided dice 20 times
13    for (int n=0; n != 20; ++n) {
14        int x = 7;
15        while(x > 6) 
16            x = 1 + std::rand()/((RAND_MAX + 1u)/6);  // Note: 1+rand()%6 is biased
17        std::cout << x << ' ';
18    }
19}

1v1 = rand() % 100;         // v1 in the range 0 to 99  --Credit goes to Clever cowfish
2v2 = rand() % 100 + 1;     // v2 in the range 1 to 100
3v3 = rand() % 30 + 1985;   // v3 in the range 1985-2014