Leetcode-1157 Online Majority Element In Subarray(子数组中占绝大多数的元素)

 1 #define _for(i,a,b) for(int i = (a);i < b;i ++)
 2 
 3 
 4 class MajorityChecker
 5 {
 6     public:
 7         vector<int> v;
 8         int hash[20003];
 9         MajorityChecker(vector<int>& arr)
10         {
11             v = arr;
12         }
13 
14         int query(int left, int right, int threshold)
15         {
16             memset(hash,0,sizeof(hash));
17             _for(i,left,right+1)
18                 hash[v[i]] ++;
19             _for(i,0,20003)
20                 if(hash[i]>=threshold)
21                     return i;
22             return -1;
23         }
24 };