Swap the number without using the thired variable.

For Example Swap A and B (A = 2000 , B = 2001) 

	Start Algorithm
		Store 0 in  num1, num2;
		Display ("Enter the num1:")
		Read num1
			num1 = num1 + num2
			num2 = num1 - num2
			num1 = num1 - num2
		Display num1
		Display num2
	Stop	
			
					

Output:  A = 2001 , B = 2000