func_code_string: #include <bits/stdc++.h>   using namespace std;   inline pair<int, int> best(pair<int, int> a, pair<int, int> b) {     if ((a.first > b.first) || ((a.first == b.first) && (a.second < b.second)))       return a;     return b;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int n, m;     string s;     cin >> n;     cin >> s;     cin >> m;     vector<vector<int> > ka(n, vector<int>(2));     vector<vector<int> > kb(n, vector<int>(2));     vector<int> kv(n);     vector<int> preva(n, -1);     if (s[0] ==  a ) {       preva[0] = 0;       ka[0][0] = 1;     }     if (s[0] ==  b ) kb[0][0] = 1;     if (s[0] ==  ? ) kv[0] = 1, preva[0] = 0;     for (int i = 1; i < n; i++) {       ka[i][0] = ka[i - 1][0];       ka[i][1] = ka[i - 1][1];       if (s[i] ==  a ) ka[i][i % 2]++;       kb[i][0] = kb[i - 1][0];       kb[i][1] = kb[i - 1][1];       if (s[i] ==  b ) kb[i][i % 2]++;       if ((s[i] ==  a ) || (s[i] ==  ? ))         preva[i] = i;       else         preva[i] = preva[i - 1];       kv[i] = kv[i - 1];       if (s[i] ==  ? ) kv[i]++;     }     vector<vector<pair<int, int> > > dp(n, vector<pair<int, int> >(2));     if (((s[0] ==  a ) || (s[0] ==  ? )) && (m <= n) && (kb[m - 1][0] == 0) &&         (ka[m - 1][1] == 0))       dp[0][1] = {1, kv[m - 1]};     for (int i = 1; i < n; i++) {       dp[i][0] = best(dp[i - 1][0], dp[i - 1][1]);       if (i + m - 1 >= n) continue;       int bada = ka[i + m - 1][(i % 2) ^ 1] - ka[i - 1][(i % 2) ^ 1];       int badb = kb[i + m - 1][i % 2] - kb[i - 1][i % 2];       if ((bada != 0) || (badb != 0)) continue;       if (i < m) {         dp[i][1] = {1, kv[i + m - 1] - kv[i - 1]};       } else {         int p = preva[i - m];         if (p < 0) {           dp[i][1] = {1, kv[i + m - 1] - kv[i - 1]};         } else {           dp[i][1] = best(dp[p][0], dp[p][1]);           dp[i][1].first++;           dp[i][1].second += kv[i + m - 1] - kv[i - 1];         }       }     }     pair<int, int> rez = best(dp[n - 1][0], dp[n - 1][1]);     cout << rez.second <<   n ;     return 0;   }   