LeetCode 704. 二分查找

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