9.最长公共子序列

 

时间复杂度n^2

debug过程

 

#include <bits/stdc++.h>
using namespace std;
const int N = 1010;
char a[N], b[N];
int dp[N][N];
int main() {
    int n, m;
    cin >> n >> m;
    cin >> a + 1 >> b + 1;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m ; j++) {
            dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
            if (a[i] == b[j]) {
                dp[i][j] = max(dp[i][j], dp[i - 1][j - 1] + 1);
            }
        }
    }
    cout << dp[n][m] << endl;
    return 0;
}