leetcode35 Search Insert Position 

 1 """
 2 Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order.
 3 You may assume no duplicates in the array.
 4 Example 1:
 5 Input: [1,3,5,6], 5
 6 Output: 2
 7 Example 2:
 8 Input: [1,3,5,6], 2
 9 Output: 1
10 Example 3:
11 Input: [1,3,5,6], 7
12 Output: 4
13 Example 4:
14 Input: [1,3,5,6], 0
15 Output: 0
16 """
17 """
18 本题提供两种解法，第一种是遍历有序的数组
19 遇到大于等于 target的位置插入
20 """
21 class Solution1:
22     def searchInsert(self, nums, target):
23         if nums[-1] < target:  #边界条件
24             return len(nums)
25         if nums[0] > target:
26             return 0
27         for i in range(len(nums)):
28             if nums[i] >= target: #！！！关键点
29                 return i
30 
31 """
32 二分法
33 对于二分法的 left right mid之间的转换 
34 目前的思路是 更换测试用例 来不断修正如何转换
35 传送门：https://www.jianshu.com/p/46b8d8a55888
36 """
37 class Solution2:
38     def searchInsert(self, nums, target):
39         if not nums:
40             return 0
41         left = 0
42         right = len(nums)
43         while left < right:
44             mid = (left+right)//2
45             if nums[mid] >= target:
46                 right = mid
47             else:
48                 left = mid + 1
49         return left

 

posted @ 2020-02-12 22:34  yawenw  阅读(122)  评论(0)    收藏  举报