[brush questions] most elements (super water king problem)

One 、 subject

OJ link
Given a size of n Array of nums , Return most of the elements . Most elements refer to the number of occurrences in an array Greater than ⌊ n/2 ⌋ The elements of .

You can assume that the array is not empty , And there are always many elements in a given array .

requirement ： Time complexity O(N) Spatial complexity O(1)

Two 、 Answer key

2.1 Ideas

The core idea ：

Detailed process ：

2.2 Source code ：

 public int majorityElement(int[] arr) {
    
       int cand=0;
       int HP=0;
        for (int i = 0; i < arr.length; i++) {
    
            if(HP==0){
    
                cand=arr[i];
                HP=1;
            }else if(cand==arr[i]){
    
                HP++;
            }else {
    
                HP--;
            }

        }
        return cand;
    }