718_maximum-length-of-repeated-subarray.js

/**
 * Title: 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.
 * Author: Hasibul Islam
 * Date: 24/04/2023
 */

/**
 * @param {number[]} nums1
 * @param {number[]} nums2
 * @return {number}
 */
var findLength = function (nums1, nums2) {
  let n1 = nums1.length;
  let n2 = nums2.length;
  let res = 0;

  let dp = new Array(n1 + 1).fill().map(() => new Array(n2 + 1).fill(0));

  for (let i = 1; i <= n1; i++) {
    for (let j = 1; j <= n2; j++) {
      if (nums1[i - 1] == nums2[j - 1]) {
        // Since we want a subarray of nums1 AND nums2
        // we need to make sure its continuous with the
        // dp[i-1][j-1] location :)
        dp[i][j] = dp[i - 1][j - 1] + 1;
        res = Math.max(res, dp[i][j]);
      }
    }
  }

  return res;
};