#include <iostream>
#include <bitset>
 
using namespace std;
 
unsigned long long binomial(unsigned n, unsigned k)
{
  if (k > n) return 0;
  unsigned result = 1;
  for (unsigned d=1; d <= k; d++) {
    result *= n--;
    result /= d;
  }
  return result;    
}
 
unsigned long long next_permutation(unsigned long long v)
{
  unsigned long long t = (v | (v - 1)) + 1;  
  return t | ((((t & -t) / (v & -v)) >> 1) - 1);
}
 
int main()
{
  const unsigned n = 5;
  const unsigned k = 3;
 
  unsigned long long permutation = (1 << k) - 1;
 
  for (unsigned int i = 0; i < binomial(n,k); ++i)
    {
      bitset<n> foo(permutation);
      cout << foo << '\n';
      permutation = next_permutation(permutation);
     }
}
 

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