https://practice.geeksforgeeks.org/problems/majority-element-1587115620/1/?category[]=Arrays#
Given an array A of N elements. Find the majority element in the array. A majority element in an array A of size N is an element that appears more than N/2 times in the array.
Example 1:
Input: N = 3 A[] = {1,2,3} Output: -1 Explanation: Since, each element in {1,2,3} appears only once so there is no majority element. Example 2:
Input: N = 5 A[] = {3,1,3,3,2} Output: 3 Explanation: Since, 3 is present more than N/2 times, so it is the majority element.
Your Task: The task is to complete the function majorityElement() which returns the majority element in the array. If no majority exists, return -1.
Expected Time Complexity: O(N). Expected Auxiliary Space: O(1).
Constraints: 1 ≤ N ≤ 107 0 ≤ Ai ≤ 106