Verify Max Heap - Amazon Top Interview Questions

Problem Statement :

Given a list of integers nums, return whether it represents a max heap. That is, for every i we have that:

nums[i] ≥ nums[2*i + 1] if 2*i + 1 is within bounds
nums[i] ≥ nums[2*i + 2] if 2*i + 2 is within bounds


0 ≤ n ≤ 100,000 where n is the length of nums

Example 1

nums = [4, 2, 3, 0, 1]


Solution :


                        Solution in C++ :

bool check(vector<int>& A, int i) {
    return (i >= A.size())
               ? true
               : ((A[i] >= ((i * 2 + 1 < A.size()) ? A[i * 2 + 1] : INT_MIN)) &
                  (A[i] >= ((i * 2 + 2 < A.size()) ? A[i * 2 + 2] : INT_MIN)) & check(A, i + 1));

bool solve(vector<int>& nums) {
    return check(nums, 0);

                        Solution in Java :

import java.util.*;

class Solution {
    public boolean solve(int[] nums) {
        for (int i = 0; i < nums.length; i++) {
            int k = 2 * i + 1;
            boolean result = true;
            if (k < nums.length)
                result = result && nums[i] >= nums[k];
            if (k + 1 < nums.length)
                result = result && nums[i] >= nums[k + 1];
            if (!result)
                return result;
        return true;

                        Solution in Python : 
class Solution:
    def solve(self, nums):
        for i in range(len(nums)):
            j = 2 * i + 1
            if j < len(nums) and nums[i] < nums[j]:
                return False
            if j + 1 < len(nums) and nums[i] < nums[j + 1]:
                return False

        return True

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