题解 | #二分查找-I#

#
# 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
#
class Solution:
    def search(self , nums: List[int], target: int) -> int:
        # write code here
        if not nums:
            return -1
        left = 0
        right = len(nums) - 1
        mid = (left + right) >> 1
        while left < right:
            if nums[mid] < target:
                left = mid+1
            if nums[mid] > target:
                right = mid - 1
            if nums[mid] == target:
                return mid
            mid = (left + right) >> 1
        if nums[left] == target:
            return left
        else:
            return -1