LeetCode 35.Search Insert Position

题目：

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

思路：

1.当target比nums[0]小时，返回0;

2.当target比nums[end]大时，返回nums.length；

3.用二分法查找start和end，使nums[start]<=target<=nums[end]：

当nums[start] == target时，返回start；否则返回end;

(未完待续)