LeetCode 718. 最长重复子数组（DP）

示例 1:
输入:
A: [1,2,3,2,1]
B: [3,2,1,4,7]
输出: 3
解释: 
长度最长的公共子数组是 [3, 2, 1]。
说明:
1 <= len(A), len(B) <= 1000
0 <= A[i], B[i] < 100

class Solution {
public:
    int findLength(vector<int>& A, vector<int>& B) {
    	int i, j, m = A.size(), n = B.size(), maxlen = 0;
    	vector<vector<int>> dp(m+1,vector<int>(n+1, 0));
    	for(i = 1; i <= m; ++i)
    	{
    		for(j = 1; j <= n; ++j)
    		{
    			if(A[i-1] == B[j-1])
    				dp[i][j] = dp[i-1][j-1]+1;
    			maxlen = max(maxlen, dp[i][j]);
    		}
    	}
    	return maxlen;
    }
};