How to swap two variables, without using third variable ?
Answers were Sorted based on User's Feedback
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 |
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 |
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 |
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 |
---------------------
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 |
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 |
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 |
Answer / xyz
Congrats to all guys who have tried this.Everything u post
here is correct
| Is This Answer Correct ? | 0 Yes | 0 No |
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C Code 
