LCS

/*
    Task    : LCS
    Author  : Phumipat C. [MAGCARI]
    Language: C++
    Created : 28 December 2022 [18:43]
*/
#include<bits/stdc++.h>
using namespace std;
int dp[110][110];
char a[110],b[110];
int main(){
    int n,m;
    scanf("%d %d",&n,&m);   // length of string a and b
    scanf(" %s %s",a+1,b+1);
    int mx = 0;
    pair<int ,int > pos;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++){
            if(a[i] == b[j])    dp[i][j] = dp[i-1][j-1] + 1;
            // Subsequence
            // dp[i][j] = max({dp[i][j],dp[i-1][j],dp[i][j-1]});
            if(mx < dp[i][j]){
                mx = dp[i][j];
                pos = {i,j};
            }
        }
    }
    printf("%d\n",mx);

    // Print longest common substring only
    // for(int i=mx-1;i>=0;i--)
    //  printf("%c",a[pos.first - i]);
    return 0;
}