[LeetCode]34. Search for a Range

34. Search for a Range

https://leetcode.com/problems/search-for-a-range/description/

与上一题很相似，原理很清晰，两次二分搜索，一次找前边界一次找后边界，不必在找到target后直接break。但我真的是太讨厌二分搜索了，边界条件实在头疼。

class Solution { public:     vector<int> searchRange(vector<int>& nums, int target) {         int l = 0, r = nums.size()-1;         vector<int> res(2,-1);         if (nums.empty()) return res;         if (nums.size()==1 && nums[0] == target) return (vector<int>){0,0};           while (l < r){             int mid = (l+r)/2;             if (nums[mid]<target) l = mid+1;             else r = mid;          }         if (nums[r]!=target) return res;         res[0] = r;         r = nums.size();///!!!         while (l < r){             int mid = (l+r)/2;             if (nums[mid]>target) r = mid;             else l = mid+1;         }         res[1] = l-1;//!!!         return res;     } };

Reference

http://www.cnblogs.com/grandyang/p/4409379.html

文章来源: [LeetCode]34. Search for a Range