查找排序數組的插入位置

題目：

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

分析：此題和上一題類似，就是利用二分搜索查找數字。
具體代碼如下：

int searchInsert(int A[], int n, int target) {
        if(n<=0)return 0;
        int l=0,r=n-1,m=l+(r-l)/2;
        while(l<r)
        {
            if(A[m]>=target)r=m;
            if(A[m]<target)l=m+1;
            m=l+(r-l)/2;
        }
        if(A[m]>=target)
           return m;
        return m+1;
    }