#include <bits/stdc++.h> #define int long long using namespace std; int n; bool vis[10]; void dfs(int x,string ans,int lst) { cout << '(' << ans << ')' << endl; for (int i = 1; i <= n; i++) if (!vis[i] && i > lst) { vis[i] = true; dfs(x + 1,ans + (char)(i + 'a' - 1),i); vis[i] = false; } } signed main() { cin >> n; dfs(1,"",0); return 0; }