题解 | #二分查找-I#

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param nums int整型一维数组 
     * @param target int整型 
     * @return int整型
     */
       public int search(int[] nums, int target) {
        if (nums.length == 0) {
            return -1;
        } else if (nums.length == 1) {
            return nums[0] == target ? 0 : -1;
        }

        int res = -1;
        int low = 0, high = nums.length - 1;
        int mid = (low + high) >> 1;
        while (low <= high) {
            if (target > nums[mid]) {
                low = mid+1;
            } else if (target < nums[mid]) {
                high = mid-1;
            } else {
                return mid;
            }
            mid = (low + high) >> 1;
        }
        return res;
    }
}