func_code_string: #include <bits/stdc++.h>   using namespace std;   signed main() {     string s;     cin >> s;     int n = s.size();     if (n == 1) {       cout << 0;       return 0;     }     int ans = 0;     int co = 1;     vector<pair<char, int> > c;     for (int i = 1; i < n; i++) {       if (s[i] != s[i - 1]) {         c.emplace_back(s[i - 1], co);         co = 0;       }       co++;     }     c.emplace_back(s[n - 1], co);     int k = c.size();     if (k % 2 == 0) {       cout << 0;       return 0;     }     for (int i = 0; i < k / 2; i++) {       if ((c[i].first != c[k - 1 - i].first) ||           (c[i].second + c[k - 1 - i].second < 3)) {         cout << 0;         return 0;       }     }     if (c[k / 2].second == 1)       cout << 0 << endl;     else       cout << c[k / 2].second + 1 << endl;   }   