shuffle algorithm

[Justin12]

Hi,

how can you implement the following?
How would you program a computer to shuffle a deck of cards (Generate a permutation of the numbers from 1 to 100, uniformly at random)

Thanks,
Justin12

[Belli]

card cards[100];

for(int i = 99; i; --i)
{
  //Generate a random number in the range from 0 to i
  //Exchange cards[i] and cards[generated random number]
}

[assdfasfd]

http://en.cppreference.com/w/cpp/algorithm/next_permutation

[SeppJ]

http://en.cppreference.com/w/cpp/algorithm/random_shuffle

[Fytch]

The approach, that Belli suggested is also known as Fisher-Yates shuffle. The mentioned std::random_shuffle uses this algorithm in some implementations.

[TNA]

#include <random>
#include <algorithm>

int main()
{
    std::vector<int> v(100);
    std:iota(v.begin(), v.end,1);
    std::random_device rd;
    std::mt19937 g(rd());
    std::shuffle(v.begin(), v.end(), g);
}