The algorithm to shuffle a std::vector to a random order is already present in the STL. It is called std::random_shuffle and can be found in the header file algorithm.
#include <algorithm> #include <iostream> #include <iterator> #include <ostream> #include <vector> //From http://www.richelbilderbeek.nl/CppStdRand.mdomShuffle.htm int main() { //Create a std::vector std::vector<int>(v); //Fill it with 10 values for (int i=0; i!=10; ++i) v.push_back(i); //Show it on screen std::cout << "Before shuffling: " << std::endl; std::copy(v.begin(),v.end(),std::ostream_iterator<int>(std::cout,"\n")); //Shuffle it std::random_shuffle(v.begin(),v.end()); //Show it on screen std::cout << "After shuffling: " << std::endl; std::copy(v.begin(),v.end(),std::ostream_iterator<int>(std::cout,"\n")); }