DAY-015-cpp-[704. 二分查找]

class Solution {
public:
    int search(vector<int>& nums, int target) {
        int left = 0, right = nums.size() - 1;
        while (left<=right) {
            int mid = left + (right - left) / 2;
            if (nums[mid] > target) {
                right = mid - 1;
            }
            else if(nums[mid]<target) {
                left = mid + 1;
            }
            else {
                return mid;
            }
        }
        return -1;
    }
};