求两个字符串的公共子串的最大长度

#include <iostream>
#include <string.h>
#include <algorithm>
using namespace std;
#define N 1100

char s[N];
char t[N];

int dp[N][N];

int main()
{
    cin >> s;
    cin >> t;
    int lens = strlen(s);
    int lent = strlen(t);
    int mx = 0;
    for (int i = 0; i < lens; i++) {
        for (int j = 0; j < lent; j++) {
            if (s[i] == t[j]) {
                if (i == 0 || j == 0) {
                    dp[i][j] = 1;
                } else {
                    dp[i][j] = dp[i - 1][j - 1] + 1;
                }

                mx = max(mx, dp[i][j]);
            }
        }
    }

    cout << mx << endl;
    return 0;
}
/*
abcde
bcd
*/