class Solution:
    def searchInsert(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: int
        """
        # Approach #1
        # if target in nums:
        #     return nums.index(target)
        # else:
        #     for index,num in enumerate(nums):
 

        #         if target < nums[0]:
        #             return 0
        #         if target > nums[-1]:
        #             return len(nums)
        #         if num < target and nums[index+1] > target:
        #             return index+1



        # Approach #2   
        # left , right = 0 , len(nums) - 1
 

        # if target < nums[left]:
        #     return 0
        # if target > nums[right]:
        #     return len(nums)
        # if target in nums:
        #     return nums.index(target)
        # while right - 1 > left :
        #     mid = ( left + right ) // 2
        #     if  target < nums[mid]:
 

        #         right = mid
        #     elif nums[mid] < target:
        #         left = mid
        #     if nums[mid] == target:
        #         return mid
        # return left + 1


        # Approach #3  簡化方法二
        i, j = 0, len(nums) - 1
        while i < j:
            mid = (j - i) // 2 + i 
            if nums[mid] < target:
                i = mid + 1
            else:
                j = mid - 1
        return i+1 if nums[i] < target else i   # 最後要寫nums[i]而不是nums[0]，因為需要處理二分查詢失敗的輸入。