#include <algorithm>
#include <iostream>
#include <vector>
 
std::vector<int> perm, chosen;
int n = 3;
 
void print(const std::vector<int>& v)
{
    for (int e : v) {
        std::cout << " " << e;
    }
    std::cout << std::endl;
}
 
void search() {
    if (perm.size() == n) /// DEAD END
    { 
        print(perm);
    } 
    else {
        for (int i = 0; i < n; i++) {
 
            if (chosen[i]) continue; /// you have already taken this in your current path , so ignore it now
 
            chosen[i] = true; /// take it , as you haven't already
            perm.push_back(i);
 
            search(); // go to the next step after taking this item
 
            chosen[i] = false; // you have done all you could do with this , now get rid of it
            perm.pop_back();
        }
    }
}
 
int main()
{
	for(int i = 1; i <= n; i++) perm.push_back(i);
	search();
}

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