func_code_string: #include <bits/stdc++.h>   using namespace std;   long long dp[5011][5011];   void solve() {     long long n, m;     cin >> n >> m;     string s1, s2;     cin >> s1 >> s2;     s1 =  .  + s1;     s2 =  .  + s2;     long long ans = 0;     for (long long i = 1; i <= n; i++) {       for (long long j = 1; j <= m; j++) {         dp[i][j] = max({0ll, dp[i - 1][j] - 1, dp[i][j - 1] - 1});         if (s1[i] == s2[j])           dp[i][j] = max(               {0ll, dp[i - 1][j] - 1, dp[i][j - 1] - 1, dp[i - 1][j - 1] + 2});         ans = max(ans, dp[i][j]);       }     }     cout << ans;   }   int32_t main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     long long t = 1;     while (t--) solve();   }   