How to generate an array of 256 distinct numbers

Question

I have this:

#include     
using namespace std;   
int main()
{
    int a[256];
    int b;
    int k;
    for (int i = 0; i < 256; i ++){
             


        

Answer 1

You could try something like this:

int main()
{
    std::vector available(256);
    int a[256];

    for (int i = 0; i < 256; ++i)
        available.push_back(i);

    for (int i = 0; i < 256; ++i)
    {
        int idx = rand() % available.size();
        a[i] = available[idx];
        available.erase(available.begin()+idx);
    }

    // use a[] as needed...

    return 0;
}