2169. Permutations

#include <stdio.h>
#include <stdlib.h>

const int N = 10;
int n;

bool used[N];

int m[N];

void rec(int pos)
{
    if(pos == n)
    {
        for(int i = 0 ; i < n ; ++i)
        {
            printf("%d ",m[i]);
        }
        puts("");

        return;
    }
    for(int i = 1 ; i <= n ; ++i)
    {
        if(!used[i])
        {
            used[i] = true;
            m[pos] = i;
            rec(pos+1);
            m[pos] = -1;
            used[i] = false;
        }
    }
    return;
}

signed main()
{
    scanf("%d",&n);

    rec(0);

    return 0;
}