#include <iostream>
#include <vector>
#include <string>
using namespace std;
 
int lcs(string s1, string s2) {
    int n = s1.size(), m = s2.size();
    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++) {
            if (s1[i-1] == s2[j-1])
                dp[i][j] = dp[i-1][j-1] + 1;
            else
                dp[i][j] = max(dp[i-1][j], dp[i][j-1]);
        }
    }
    return dp[n][m];
}
 
int main() {
    string s1 = "ABCBDAB", s2 = "BDCABA";
    cout << "Length of LCS: " << lcs(s1, s2) << endl;
    return 0;
}
 

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