Обмен значениями двух численных переменных

Есть 3 очень простых способа поменять значения 2х числовых переменных без использования временной переменной

Может кому-нибудь пригодится

Релизациях на Java

1) Сумма-Разность

int a = 10;

int b = 20;

System.out.println("value of a and b before swapping, a: " + a +" b: " + b);

//swapping value of two numbers without using temp variable

a = a+ b; //now a is 30 and b is 20

b = a -b; //now a is 30 but b is 10 (original value of a)

a = a -b; //now a is 20 and b is 10, numbers are swapped

System.out.println("value of a and b after swapping, a: " + a +" b: " + b);

Output:

value of a and b before swapping, a: 10 b: 20

value of a and b after swapping, a: 20 b: 10

2) Magic XOR

A       B       A^B (A XOR B)

0       0       0 (zero because operands are same)

0       1       1

1       0       1 (one because operands are different)

1       1       0

int a = 2; //0010 in binary

int b = 4; //0100 in binary

      

System.out.println("value of a and b before swapping, a: " + a +" b: " + b);

       

//swapping value of two numbers without using temp variable and XOR bitwise operator     

a = a^b; //now a is 6 and b is 4

b = a^b; //now a is 6 but b is 2 (original value of a)

a = a^b; //now a is 4 and b is 2, numbers are swapped

      

System.out.println("value of a and b after swapping using XOR bitwise operation, a: " + a +" b: " + b);

value of a and b before swapping, a: 2 b: 4

value of a and b after swapping using XOR bitwise operation, a: 4 b: 2

3) Произведение-Деление

int a = 6;

int b = 3;

System.out.println("value of a and b before swapping, a: " + a +" b: " + b);

//swapping value of two numbers without using temp variable using multiplication and division

a = a*b; //now a is 18 and b is 3

b = a/b; //now a is 18 but b is 6 (original value of a)

a = a/b; //now a is 3 and b is 6, numbers are swapped

System.out.println("value of a and b after swapping using multiplication and division, a: " + a +" b: " + b);

Output:

value of a and b before swapping, a: 6 b: 3

value of a and b after swapping using multiplication and division, a: 3 b: 6

Как видите количество действий не отличается от варианта с временной переменной.