提交时间:2024-03-09 08:49:06
运行 ID: 136343
#include <bits/stdc++.h> using namespace std; int res[9], cnt = 0, n, us[9]; void dfs(int cur) { if (cur > n) { for (int i = 1; i <= n; i++) cout << res[i]; cout << endl; cnt++; return; } for (int i = 1; i <= n; i++) { if (!us[i]) { us[i] = true; res[cur] = i; dfs(cur + 1); us[i] = false; } } } int main() { cin >> n; dfs(1); cout << cnt << endl; }