#include <iostream> #include <string> using namespace std; bool isPalindrome(string s, int left, int right) { while (left < right) { if (s[left] != s[right]) { return false; } left++; right--; } return true; } int main() { string s; cin >> s; int n = s.length(); for (int i = 0; i < n; i++) { // 以单个字符为中心 for (int j = 1; j <= 2; j++) { if (i - j >= 0 && i + j < n && s[i - j] == s[i + j]) { cout << "Yes" << endl; return 0; } } // 以两个字符为中心 if (i + 1 < n && s[i] == s[i + 1]) { cout << "Yes" << endl; return 0; } if (i + 2 < n && s[i] == s[i + 2]) { cout << "Yes" << endl; return 0; } } cout << "No" << endl; return 0; }