29 数组中出现次数超过一半的数字

 1 class Solution {
 2 public:
 3     int MoreThanHalfNum_Solution(vector<int> numbers) {
 4         if (numbers.empty())
 5             return 0 ;
 6         int majority = numbers[0] ;
 7         int cnt = 1 ;
 8         for(int i = 1 ; i < numbers.size() ; i++){
 9             if (cnt == 0){
10                 majority = numbers[i] ;
11                 cnt = 1 ;
12             }else if (numbers[i] == majority){
13                 cnt++ ;
14             }else{
15                 cnt-- ;
16             }
17         }
18         cnt = 0 ;
19         for(int i = 0 ; i < numbers.size() ; i++){
20             if (numbers[i] == majority)
21                 cnt++ ;
22         }
23         if (cnt > numbers.size()/2)
24             return majority ;
25         else
26             return 0 ;
27     }
28 };