[Leetcode]Search Insert Position

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.

典型的二分查找问题，注意越界了的返回值就好了。

 1 class Solution {
 2 public:
 3     int searchInsert(int A[], int n, int target) {
 4         int low=0;int high=n-1;
 5         while(low<=high){
 6             int mid=(low+high)>>1;
 7             if(target==A[mid])
 8             return mid;
 9             if(target<A[mid])
10             high=mid-1;
11             else
12             low=mid+1;
13         }
14         if(high<0) return 0;
15         if(low>n) return n;
16         return low;
17     }
18 };