题解 | #二分查找-II# #基本左右边界#

#coding:utf-8
#
# 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
#
# 如果目标值存在返回下标，否则返回 -1
# @param nums int整型一维数组 
# @param target int整型 
# @return int整型
# 注意：不确定最终返回值是left、right、还是mid的话，直接print 三个val看看就好
#
class Solution:
    def search(self , nums , target ):
        # write code here
        #init
        n = len(nums)
        if n == 0:
            return -1
        left = 0
        right = n - 1
        #process
        mid = left + (right - left) // 2
        while left < right:
            mid = left + (right - left) // 2
            if nums[mid] >= target:
                right = mid
            else:
                left = mid + 1
        #print ("left, mid, right: ", left, mid, right)
        if nums[left] == target:
            return left
        return -1