链接：

题意：

    A palindrome is a symmetrical string, that is, a string read identically from left to right as well as from right to left. For example, ”a”、”aba”、“abba” are palindrome and “abc”、”aabb” are not.

    Let’s define a new function f(s).

    For some string s, f(s) is the length of the longest palindrome substring.

    Now you should decide for the given string s, whether f(s) is great than 1.

    The string s only contains lowercase letters.

思路：

找类似aa， aba这种的回文串就行了

代码：

#include 
     
       using namespace std; typedef long long LL;const int MAXN = 3e5 + 10;const int MOD = 1e9 + 7;int n, m, k, t; int main(){    cin >> n;    string s;    cin >> s;    bool flag = false;    for (int i = 1;i < n-1;i++)    {        if (s[i] == s[i-1] || s[i-1] == s[i+1])        {            flag = true;            break;        }    }    if (s[n-1] == s[n-2])        flag = true;    if (flag)        cout << "YES" << endl;    else        cout << "NO" << endl;     return 0;}