func_code_string: #include <bits/stdc++.h>   using namespace std;   using ld = long double;   template <class T>   inline T gcd(T a, T b) {     return !a ? b : gcd(b % a, a);   }   template <class T>   inline T lcm(T a, T b) {     return (a * b) / gcd(a, b);   }   mt19937 rnd(time(0));   const int INF = 1e9;   const long long LLINF = 1e15;   void solve() {     int n, m;     cin >> n >> m;     string a, b;     cin >> a >> b;     int ans = 0;     vector<vector<int>> dp(n + 1, vector<int>(m + 1, 0));     for (int i = 1; i <= n; i++) {       for (int j = 1; j <= m; j++) {         dp[i][j] = max(0, max(dp[i - 1][j], dp[i][j - 1]) - 1);         if (a[i - 1] == b[j - 1]) {           dp[i][j] = max(dp[i][j], dp[i - 1][j - 1] + 2);         }         ans = max(ans, dp[i][j]);       }     }     cout << ans <<   n ;     return;   }   signed main() {     ios_base ::sync_with_stdio(0);     cin.tie(0), cout.tie(0);     int t = 1;     while (t-- > 0) {       solve();     }     return 0;   }   