leetcode maximum-length-of-repeated-subarray/submissions

718. Maximum Length of Repeated Subarray

Medium

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Given two integer arrays A and B, return the maximum length of an subarray that appears in both arrays.

Example 1:

Input:
A: [1,2,3,2,1]
B: [3,2,1,4,7]
Output: 3
Explanation: 
The repeated subarray with maximum length is [3, 2, 1].

Note:

1. 1 <= len(A), len(B) <= 1000
2. 0 <= A[i], B[i] < 100

依次遍历两个数组，找到相同元素后，查询上次相同到现在的长度加一，用max记录最大值。

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