Java SE(21) extension: four ways to exchange two numbers

Method 1: Use an intermediate variable to exchange values.

public class JiaoHuan1{
	public static void main(String[] args){
		int a=5,b=10;    //定义两个变量
		System.out.println("交换前："+a+"\t"+b);
		
		int t;   //引入一个中间变量
		//交换变量
		t=a;
		a=b;
		b=t;
	
		System.out.println("交换后："+a+"\t"+b);
	}
}

 operation result:

  

Method 2: Use the method of summing and subtracting two numbers for data exchange. The disadvantage is that if the values ​​of x and y are too large, the value of int will lose accuracy.

public class JiaoHuan2{
	public static void main(String[] args){
		int a=5,b=10;    //定义两个变量
		System.out.println("交换前："+a+"\t"+b);
		
        //交换变量
		a=a+b;  //a=5+10=15
		b=a-b;  //b=15-10=5
		a=a-b;  //a=15-5=10
	
		System.out.println("交换后："+a+"\t"+b);
	}
}

 operation result:

 

Method 3: Use bit operations to exchange data. The principle of the idea is that a number is XOR the same number twice, and the result is still that number, and it will not exceed the range of int.

public class JiaoHuan3{
	public static void main(String[] args){
		int a=5,b=10;    //定义两个变量
		System.out.println("交换前："+a+"\t"+b);
		
		//交换变量
		a=a^b;  
		b=a^b;  //b=(a^b)^b
		a=a^b;  //a=(a^b)^a
	
		System.out.println("交换后："+a+"\t"+b);
	}
}

operation result:

Method 4: directly exchange variables when printing out

public class JiaoHuan4{
	public static void main(String[] args){
		int a=5,b=10;    //定义两个变量
		System.out.println("交换前："+a+"\t"+b);
	
		System.out.println("交换后："+b+"\t"+a);
	}
}

operation result: