0718. Maximum Length of Repeated Subarray

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

Description

Given two integer arrays nums1 and nums2, return the maximum length of a subarray that appears in both arrays.

Example 1:

**Input:** nums1 = [1,2,3,2,1], nums2 = [3,2,1,4,7]
**Output:** 3
**Explanation:** The repeated subarray with maximum length is [3,2,1].

Example 2:

**Input:** nums1 = [0,0,0,0,0], nums2 = [0,0,0,0,0]
**Output:** 5

Constraints:

• 1 <= nums1.length, nums2.length <= 1000

• 0 <= nums1[i], nums2[i] <= 100

ac1: 2D dp

class Solution {
    public int findLength(int[] A, int[] B) {
        // edge cases
        if (A.length == 0 || B.length == 0) return 0;

        int lena = A.length, lenb = B.length, maxLen = 0;
        int[][] dp = new int[lena+1][lenb+1];
        for (int r = 1; r < dp.length; r++) {
            for (int c = 1; c < dp[0].length; c++) {
                if (A[r-1] == B[c-1]) {
                    dp[r][c] = dp[r-1][c-1] + 1;
                    maxLen = Math.max(maxLen, dp[r][c]);
                }

            }
        }

        return maxLen;
    }
}

/*
2D dp
*/