【leetcode】Search Insert Position

题目描述：

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.

You may assume no duplicates in the array.

Here are few examples.

[1,3,5,6], 5 → 2

[1,3,5,6], 2 → 1

[1,3,5,6], 7 → 4

[1,3,5,6], 0 → 0

解题思想：

完完全全的二分嘛

class Solution:

# @param A, a list of integers

# @param target, an integer to be inserted

# @return integer

def searchInsert(self, A, target):

l = len(A)

left = 0

right = l-1

while left <= right:

mid = (left + right) / 2

if A[mid] == target:

return mid

elif A[mid] < target:

left = mid + 1

elif A[mid] > target:

right = mid - 1

return left

s = Solution()
a = [1,3,5,6]
print s.searchInsert(a,5)
print s.searchInsert(a,2)
print s.searchInsert(a,7)
print s.searchInsert(a,0)