leetcood学习笔记-35-二分法

题目：

第一次提交;

class Solution:
    def searchInsert(self, nums: List[int], target: int) -> int:
        for i in range(len(nums)):
            if nums[i] >= target :
                return i
            if i == (len(nums)-1) and nums[i]<target:
                return i+1
                

法二：

class Solution:
    def searchInsert(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: int
        """
        if target in nums:
            return nums.index(target)
        else:
            nums.append(target)
            nums.sort()
            return nums.index(target)

方法三;二分法

class Solution:
    def searchInsert(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: int
        """
        low = 0
        high = len(nums)
        while low < high:
            mid = low + (high - low)//2#Python 的//才是取整数商舍余，/不取整 会得到小数商（Python2中3//2 3/2都是取整，Python3中3//2是取整，3/2是浮点。）
            if nums[mid] > target:
                high = mid
            elif nums[mid] < target:
                low = mid +1
            else:
                return mid
        return low