Search Insert Position (Medium)

Description

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

Analysis

二分搜索题。

My Solution

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//C++
class Solution {
public:
    int searchInsert(int A[], int n, int target) {
        int l = 0 , r = n-1 ,mid;
        while(l<=r){
            mid = l + ((r-l)>>1);
            if(A[mid]>target)
                r = mid-1; // when r = mid,then while(l<r)
            else
                l = mid+1;
            if(A[mid]==target)
                return mid;
        }
        return l;
    }
};