leetcode

0275.cpp (474B)

 class Solution {
   public:
     int hIndex(const vector<int> &citations) const {
         const int n = size(citations);
         int low = 0, high = n - 1;
 
         while (low <= high) {
             const int mid = low + (high - low) / 2;
             if (citations[mid] == n - mid) return citations[mid];
             if (citations[mid] > n - mid)
                 high = mid - 1;
             else
                 low = mid + 1;
         }
 
         return n - high - 1;
     }
 };