LeetCode718. Maximum Length of Repeated Subarray(Medium)

原题：https://leetcode.com/problems/maximum-length-of-repeated-subarray/description/

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

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通过循环的方式，讨论两个字符串所有可能的相对位置。

位置1：

1 2 3 5 4    5 4 1 4 2

位置2：

1 2 3 5 4      5 4 1 4 2

在当前我位置中寻找匹配的最大子串，然后再和其他位置 的情况对比，选出所有情况的最大子串。

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class Solution {public:    int cnt(vector<int>& A, vector<int>& B, int i) {        int c = 0, last = 0;        for (int j = 0; j < B.size(); j++) {            if (c > last) last = c;            if (i + j < 0) continue;            if (i + j >= A.size()) {                break;            }            if (A[i + j] == B[j]) c++;            if (c > last) last = c;            if (A[i + j] != B[j]) c = 0;        }        return last;    }    int findLength(vector<int>& A, vector<int>& B) {        int max = 0;        int m = A.size(), n = B.size();        for (int i = 1 - n; i < m; i++) {            int tmp = cnt(A, B, i);            if (tmp > max) max = tmp;        }        return max;    }};

54 / 54 test cases passed.
Status: Accepted
Runtime: 95 ms