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：使用二分查找
<pre name="code" class="cpp">#include <iostream>
#include <vector>
using namespace std;
/*
在一个排好序的数组中找到一个元素合适的插入位置
可以使用二分查找的方式进行查找
*/
int InsertPos(vector<int>& vec,int key)
{
int mid,begin=0,end = vec.size()-1;
while(begin<=end)
{
mid = begin + (end-begin)/2;
if(vec[mid] == key)
return mid;
else if(vec[mid] < key)
begin = mid+1;
else
end = mid-1;
}
return mid >=vec.size()-1?vec.size():mid;
}
int main()
{
int array[]={1,8,9,12,15};
vector<int> vec(array,array+sizeof(array)/sizeof(int));
cout<<InsertPos(vec,100);
return 0;
}Search Insert Position--LeetCode
原文：http://blog.csdn.net/yusiguyuan/article/details/44748361