169. Majority Element_Easy(map.put(key, map.getOrDefault(key, 0) + 1))

Given an array nums of size n, return the majority element.

The majority element is the element that appears more than ⌊n / 2⌋ times. You may assume that the majority element always exists in the array.

Example One:

Input: nums = [3,2,3]
Output: 3

Example Two:

Input: nums = [2,2,1,1,1,2,2]
Output: 2

 Solution:

class Solution {
    public int majorityElement(int[] nums) {
        int len = nums.length;
        int max = 0;
        HashMap<Integer, Integer> map = new HashMap<>();
        for(Integer k : nums){
            map.put(k,map.getOrDefault(k,0)+ 1);
        }

        for(int i = 0; i < len; i++){
           
            int val = nums[i];
            if(map.get(val) > len / 2){
                max = val;
            }
        }
        return max;
    }
}

Hints:

Logics:

• use the map to sort the array
• iterate the nums, and find the majority of the val
• use the hints in the description

Tips:

• Practice makes perfect
• Try to google and the notes