#include<bits/stdc++.h> #define int long long using namespace std; namespace Fast{ //注:快读快写与CCF函数不能一起用，不然可能会趋势 inline int fr(){ register int x = 0,f = 1; static char c = getchar(); while (c < '0' || c > '9'){ if (c == '-'){ f = -1; } c = getchar(); } while (c >= '0' && c <= '9'){ x = (x << 1) + (x << 3) + (c ^ 48); c = getchar(); } return x * f; } inline void fw(int x){ if (x == 0){ putchar('0'); return ; } if (x < 0){ putchar('-'); x = -x; } stack <char> s; while (x){ s.push(x % 10 + 48); x /= 10; } while (!s.empty()){ putchar(s.top()); s.pop(); } } inline void DEBUG(){ puts("awa"); } inline void CCF(){ //原来想叫CINCOUTFASTER的结果发现缩写竟然是CCF(doge) ios::sync_with_stdio(false); cin.tie(0),cout.tie(0); } } using namespace Fast; bool f[10]; int res[10],n,ans; void dfs(int cur){ if (cur > n){ for (int i = 1;i <= n;i++){ fw(res[i]); } putchar('\n'); ans++; return ; } for (int i = 1;i <= n;i++){ if (f[i]){ continue; } f[i] = true; res[cur] = i; dfs(cur + 1); f[i] = false; } } signed main(){ n = fr(); dfs(1); fw(ans); return 0; }