如果k为0直接输出1,否则如果s为回文串的话输出1,其他情况输出2(经过一次变换后必然为回文)。注意不能特判k = 1的情况,用这个样例hack了一发23333
#include <bits/stdc++.h> #define pii pair<int,int> #define pb push_back using namespace std; int n, k; void solve() { cin >> n >> k; string s; cin >> s; if(k == 0) { cout << 1 << endl; return; } else { string ss = s; reverse(ss.begin(), ss.end()); if(ss == s) cout << 1 << endl; else cout << 2 << endl; return; } } int main() { int T = 1; cin >> T; while(T--) { solve(); } return 0; } // 1 // 2 1 // ab
Your friends Alice and Bob practice fortune telling.
Fortune telling is performed as follows. There is a well-known array