[LUOGU] P2543 [AHOI2004]奇怪的字符串

LCS

//Writer:GhostCai && His Yellow Duck
#include<iostream>
#include<cstring>
#define MAXN 5000
using namespace std;
char s[MAXN],t[MAXN];
int lens,lent;
int f[MAXN][MAXN];
int main() {
    cin>>s+1>>t+1;
    memset(f,0,sizeof(f));
    lens=strlen(s+1);
    lent=strlen(t+1);
    for(int i=1; i<=lens; i++) {
        for(int j=1; j<=lent; j++) {
            if(s[i]==t[j]) {
                f[i][j]=f[i-1][j-1]+1;
            } else {
                f[i][j]=max(f[i-1][j],f[i][j-1]);
            }
        }
    }
    cout<<f[lens][lent]<<endl;
    return 0;
}