LeetCode704. 二分查找

题目传送门：704题

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

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