func_code_string: #include <bits/stdc++.h>   using namespace std;   void solve() {     string s;     cin >> s;     int n = s.length();     int r = 0;     vector<int> fin(3, -1);     fin[0] = 0;     vector<int> z(n + 1);     for (int i = 1; i <= n; i++) {       r = (r + s[i - 1] -  0 ) % 3;       z[i] = z[i - 1];       if (fin[r] != -1) z[i] = max(z[i], z[fin[r]] + 1);       fin[r] = i;     }     cout << z[n] << endl;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int tst = 1;     while (tst--) solve();     return 0;   }   