终于知道两个模板的区别了！【手绘漫画】图解LeetCode之在排序数组中查找元素的第一个和最后一个位置（LeetCode 34）

int left=0;
int right=nums.size()-1;
while(left<right){
    int mid=left+right>>1;
    if(nums[mid]>=target){
        right=mid;
    }
    else{
        left=mid+1;
    }
}
return left;

int left=0;
int right=nums.size()-1;
while(left<right){
    int mid=(left+right+1)>>1;
    if(nums[mid]<=target){
        left=mid;
    }
    else{
        right=mid-1;
    }
}
return right;

class Solution {
public:
    vector<int> searchRange(vector<int>& nums, int target) {
        if(nums.empty()) return {-1,-1};

        int left=0;
        int right=nums.size()-1;
        while(left<right){
            int mid=(left+right)>>1;
            if(nums[mid]>=target){
                right=mid;
            }
            else{
                left=mid+1;
            }
        }
        if(nums[left]!=target) return {-1,-1};
        int start=left;

        left=0;
        right=nums.size()-1;
        while(left<right){
            int mid=(left+right+1)>>1;
            if(nums[mid]<=target){
                left=mid;
            }
            else{
                right=mid-1;
            }
        }
        if(nums[left]!=target) return {-1,-1};
        int end=right;
        
        return {start,end};
    }
};