[leetcode]Search Insert Position

二分查找的小变化。简单题。

public class Solution {
    public int searchInsert(int[] A, int target) {
        // Start typing your Java solution below
        // DO NOT write main() function
        return searchInsert(A, target, 0, A.length - 1);
    }
    
    public int searchInsert(int[] A, int target, int left, int right) {
        int mid = (left + right) / 2;
    	if (A[mid] == target) return mid;
    	
    	if (A[mid] < target) {
    		if (mid+1 > right) {
    			return mid+1;
    		}
    		return searchInsert(A, target, mid+1, right);
    	}
    	else // A[mid] > target 
    	{
    		if (mid-1 < left){
    			return mid;
    		}
    		return searchInsert(A, target, left, mid-1);
    	}
    }
}