Lâm

#include <iostream>

using namespace std;

int n, k;
int a[100];
bool select[100];

void print(int a[], int n) {
    cout << endl;
    for (int i = 1; i <= n; ++i)
        cout << a[i] << " ";
}

void list(int k, int pos) {
    for (int i = 1; i <= n; ++i) {
        if (!select[i]) {
            a[pos] = i;
            select[i] = true;
            if (pos == k) print(a, k);
            else list(k, pos + 1);
            select[i] = false;
        }
    }
}

int main()
{

    cout << "n = "; cin >> n;
    cout << "k = "; cin >> k;

    for (int i = 1; i <= k; ++i) select[i] = false;

    list(k, 1);
}