题目链接：最长公共子序列

#include <iostream>
#include <algorithm>

using namespace std;

const int N = 1010;

int n, m;
char a[N], b[N];
int f[N][N];

int main()
{
    cin >> n >> m;
    
    cin >> a + 1 >> b + 1;
    
    for(int i = 1; i <= n; i ++)
        for(int j = 1; j <= m; j ++)
        {
            f[i][j] = max(f[i - 1][j], f[i][j - 1]);
            if(a[i] == b[j]) f[i][j] = max(f[i][j], f[i - 1][j - 1] + 1);
        }
        
    cout <<f[n][m] << endl;
    
    return 0;
}