/***
 * 704. 二分查找
 * https://leetcode-cn.com/problems/binary-search/
 * date:2021/08/06
 * 笔记：二分查找的模板题
 */
public class _704_二分查找 {
    public int search(int[] nums, int target) {
        int left = 0;
        int right = nums.length-1;
        int mid = (left+right)/2;
        while(nums[mid]!=target&&left<right){
            if(nums[mid]<target){
                left = mid+1;
            }else if(nums[mid]>target){
                right = mid-1;
            }
            mid = (left+right)/2;
        }
        if(nums[mid]==target) return mid;
        return -1;
    }
}