C++ 代码

#include <iostream>
#include <algorithm>
#include <set>
#include <vector>
using namespace std;

int main() {
    int n, m;
    cin >> n >> m;
    vector<int> num(n);
    for (int i = 0; i < m; ++i) {
        num[i] = 1;
    }
    for (int i = m; i < n; ++i) {
        num[i] = 0;
    }
    set<vector<int>> cnt;
    do {
        vector<int> ans;
        for (int i = 0; i < n; ++i) {
            if (num[i] == 1) {
                ans.push_back(i + 1);
            }
        }
        sort(ans.begin(), ans.end());
        if (cnt.find(ans) == cnt.end()) {
            for (int i = 0; i < m; ++i) {
                cout << ans[i] << ' ';
            }
            cnt.insert(ans);
            cout << endl;
        }
    } while (prev_permutation(num.begin(), num.end()));
    return 0;
}