动态规划-LCS最长公共子序列

#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
using namespace std;
//LCS 
const int MAXN = 1005;
 
int DP[MAXN][MAXN];
 
int main()
{
    string a;
    string b;
    while(cin >> a >> b)
    {
        int l1 = a.size();
        int l2 = b.size();
        memset(DP, 0, sizeof(DP)); 
        for(int i = 1; i <= l1; i++)
            for(int j = 1; j <= l2; j++)
                if(a[i - 1] == b[j - 1])
                    DP[i][j] = max(DP[i][j], DP[i - 1][j - 1] + 1);
                else
                    DP[i][j] = max(DP[i][j - 1], DP[i - 1][j]);
        printf("%d\n", DP[l1][l2]);
    }
    return 0;
}