LCS

#include<bits/stdc++.h>
using namespace std;
int lcs(string a,string b,int c,int d)
{
    int len[c+5][d+5];
    for (int i = 0; i <= c; i++)
    {
    for (int j = 0; j<= d; j++)
    {
    if (i==0 || j==0)
    len[i][j] = 0;
    else if (a[i-1] == b[j-1])
    len[i][j]=1 + len[i-1][j-1];
    else
    len[i][j]=max(len[i-1][j],len[i][j-1]);

}
}
return len[c][d];
}
    int main()
    {
    string a,b;
    int c,d;
    cin>>a>>b;
    c=a.size();
    d=b.size();
    cout<<lcs(a,b,c,d)<<endl;

    return 0;
}