二分法查找

package com.learning.algorithm;

public class BinarySearch {
    
    public int binSearch(int[] arrValue, int start, int end, int key){
        int result = -1;
        
        int mid = (start+end)/2;
        
        if(start > end){
            return result;
        }
        
        if(arrValue[mid]==key){
            result = mid;
        }else if(key<arrValue[mid]){
            result = binSearch(arrValue,start,mid-1,key);
        }else if(key>arrValue[mid]){
            result = binSearch(arrValue,mid+1,end,key);
        }
        
        return result;
    }
    
    public static void main(String[] args) {
        int[] arrValue = {3,5,11,17,21,23,28,30,32,50,64,78,81,95,101}; 
        BinarySearch bs = new BinarySearch();
        int result = bs.binSearch(arrValue,0, arrValue.length-1, 17);
        System.out.println("the position of the array is :"+result);
    }
}