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.

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

1.恶心版  虽然没超时，，

public class Solution {    public int searchInsert(int[] A, int target) {        if(A==null)        return 0;                int index=0;        for(int i=0;i<A.length;i++){        if((i+1)<=(A.length-1)&&target>A[i]&&target<=A[i+1])        index=i+1;        if(target>A[A.length-1])        index=A.length;        if(target<=A[0])        index=0;        }        return index;    }}

2.二分法

public class Solution {    public int searchInsert(int[] A, int target) {        int index=0;        int l=0;        int r=A.length-1;        while(l<=r){            int mid=(l+r+1)/2; //mid向上取整哦             if(A[mid]>target)            r=mid-1; //右边边界向左缩一个            else if(A[mid]<target)            l=mid+1;            else return mid;        }        return l;    }}