#include <iostream>
#include <vector>
using namespace std;
 
void generatePermutations(vector<int> &perm, int start) {
    if (start == perm.size()) { // Điều kiện dừng
        for (int x : perm) cout << x << " ";
        cout << endl;
        return;
    }
    for (int i = start; i < perm.size(); i++) {
        swap(perm[start], perm[i]); // Hoán đổi phần tử
        generatePermutations(perm, start + 1); // Gọi đệ quy
        swap(perm[start], perm[i]); // Backtrack (khôi phục trạng thái ban đầu)
    }
}
 
int main() {
    vector<int> perm = {1, 2, 3};
    generatePermutations(perm, 0);
    return 0;
}

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