Apple Data Engineer Interview Questions

Tiago R. - "function isPalindrome(s, start, end) { while (s[start] === s[end] && end >= start) { start++; end--; } return end <= start; } function longestPalindromicSubstring(s) { let longestPalindrome = ''; for (let i=0; i < s.length; i++) { let j = s.length-1; while (s[i] !== s[j] && i <= j) { j--; } if (s[i] === s[j]) { if (isPalindrome(s, i, j)) { const validPalindrome = s.substring(i, j+1"See full answer

Vaibhav D. - "Make current as root. 2 while current is not null, if p and q are less than current, go left. If p and q are greater than current, go right. else return current. return null"See full answer

Chen J. - "Leetcode 347: Heap + Hashtable Follow up question: create heap with the length of K instead of N (more time complexity but less space )"See full answer

Relynn may silver B. - "import java.util.Arrays; import java.util.stream.Collectors; class Main { // Recursive function to print all combinations of numbers from \i\ to \n\ // having sum \n. The index\ denotes the next free slot in the output array \out\ public static void printCombinations(int i, int n, int[] out, int index) { // if the sum becomes n, print the combination if (n == 0) { System.out.println(Arrays.stream(out).limit(index) .boxed().collect(Collectors.toList())); } // start from the previous e"See full answer

Prashant Y. - "The height of a binary tree is the maximum number of edges from the root node to any leaf node. To calculate the height of a binary tree, we can use a recursive approach. The basic idea is to compare the heights of the left and right subtrees of the root node, and return the maximum of them plus one."See full answer