LeetCode Majority Element

Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times.

You may assume that the array is non-empty and the majority element always exist in the array.

Credits:
Special thanks to @ts for adding this problem and creating all test cases.

public class Solution {
    public int majorityElement(int[] num) {
        int length=num.length;
        if (length==1) {
            return num[0];
        }
        HashMap<Integer, Integer> map =new HashMap<>();
        for (int i = 0; i < length; i++) {
            if (!map.containsKey(num[i])) {
                map.put(num[i], 1);
            }else {
                int value=map.get(num[i])+1;
                if (value>length/2) {
                    return num[i];
                }else {
                    map.put(num[i], value);
                }
                
                
            }
        }
        return 0;
    }
}