How to swap two variables, without using third variable ?

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How to swap two variables, without using third variable ?..

Answer / marutikutre

x = y | (y=x)-x;

&
a=a*b/(b=a); provided either of a or b is not 0

Is This Answer Correct ?    1 Yes 0 No

How to swap two variables, without using third variable ?..

Answer / adi

answer no. 3 wont work in case of b=0!!!

Is This Answer Correct ?    1 Yes 0 No

How to swap two variables, without using third variable ?..

Answer / mrx

In assembly language you could use "xchg" instruction witch
swaps the two variables in one instruction.

/* swaps %dest <-> %source */
xchg %dest, %source


/* inline assambly example for C language */
void swap(int register *x, register int *y)
{
asm("xchg %0, %1;" \
: "=r"(*x), "=r"(*y)
: "0"(*x), "1"(*y)
);
}

This is the fastest method you can achieve in hand
optimization. I think C compiler will do the same trick if
possible.

Is This Answer Correct ?    1 Yes 0 No

How to swap two variables, without using third variable ?..

Answer / simhachalam lakkakula

Answer 4 get fail for the following values

Before: a= 219455078, b= -747788332
After: a= -875186568, b= 1

Is This Answer Correct ?    1 Yes 0 No

How to swap two variables, without using third variable ?..

Answer / simhachalam lakkakula

Answer 4
Logic:
a=a*b;
b=a/b;
a=a/b;

get fail for the following values

Before: a= 219455078, b= -747788332
After: a= -875186568, b= 1

Is This Answer Correct ?    1 Yes 0 No

How to swap two variables, without using third variable ?..

Answer / suresh bhandari

---------------------
a=a*b
b=a/b
a=a/b
---------------------
a=a+b
b=a-b
a=a-b
----------------------
a = a Xor b
b= a Xor b
a= a Xor b
----------------------
all above three methods are correct, i hv checked...

Is This Answer Correct ?    2 Yes 1 No

How to swap two variables, without using third variable ?..

Answer / d

a=a-b
b=b+a
a=b-a


is this wrong?

Is This Answer Correct ?    14 Yes 14 No

How to swap two variables, without using third variable ?..

Answer / rahul

I am new in C/C++.
How to write the program for second answer. Does it
automatically convert the numbers in binary by using ^ sign.

:}

Is This Answer Correct ?    0 Yes 0 No

How to swap two variables, without using third variable ?..

Answer / devarajan.k

a[12]=name
b[20]=name
Here the size 12 & 25 has no effect hence we can change
the size
a[]=name
b[]=name

Is This Answer Correct ?    0 Yes 0 No

How to swap two variables, without using third variable ?..

Answer / poojamnagal

Num1 = 5
Num2 = 7

Num1 = 5+7 = 12
Num2 = 12- 7 = 5
Num1 = 12-5 = 7

So, Now Num1 = 7
Num2 = 5

Is This Answer Correct ?    2 Yes 2 No

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