想写个折半查找的程序发现死循环，求解原因。

[刀刀很高]

package com.itheima.Day05;

public class ArrayFun {
	public static void main(String[] args) {
		int[]arr={3,6,8,12,19,36,444};
		
		
		System.out.println(getIndex(arr,444));
		
	}
	public static int  getIndex(int[]arr,int key){
		int min=0;
		int max=arr.length-1;
		int mid= (min+max)/2;
		while(min<=max){
			
			
			if(key>arr[mid])
				min=mid+1;
			if(key<arr[mid])
				max=mid-1;
			if(key==arr[mid])
				return mid;
		}
		return -1;
	}
}

[刀刀很高]

package com.itheima.Day05;

public class ArrayFun {
	public static void main(String[] args) {
		int[]arr={3,6,8,12,19,36,444};
		
		
		System.out.println(getIndex(arr,444));
		
	}
	public static int  getIndex(int[]arr,int key){
		int min=0;
		int max=arr.length-1;
		int mid= (min+max)/2;
		while(min<=max){
			
			
			if(key>arr[mid])
				min=mid+1;
			if(key<arr[mid])
				max=mid-1;
			if(key==arr[mid])
				return mid;
		}
		return -1;
	}
}

[qq_28905485]

[kx00450]

你判断后mid 值没变

public static int getIndex(int[] arr, int key) {
		int min = 0;
		int max = arr.length - 1;
		int mid = (min + max) / 2;
		while (min <= max) {
			if (key > arr[mid])
				min = mid + 1;
			    mid =  (min + max) / 2;
			if (key < arr[mid])
				max = mid - 1;
			    mid =  (min + max) / 2;
			if (key == arr[mid])
				return mid;
		}
		return -1;
	}

[iamjsber]

可以小伙子

[小鸡吃石子]

mid没更新啊

[neversaygodbye]

将mid的赋值放在循环内，只在循环外定义 int mid; while(min<=max){ mid= (min+max)/2;