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Values swapping in C#

Anybody please explain what is happening in this program Hi, Anybody please help me understand what is happening in this program a = a ^ b ^ (b = a); How this like is swapping both of the values at once https://code.sololearn.com/cVO10ccDJ4No/

2nd Apr 2022, 12:12 PM
Mahad Ahmed
Mahad Ahmed - avatar
4 Answers
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Mahad Ahmed the expression evaluates from left to right. Understand that bitwise xor (^) is a bit toggle. Wherever there is a 1 bit in the right operand, it will toggle the same bit from the left operand to its opposite value. A 0 bit causes no change. a^0 = a When you xor a number with itself, you get zero. a^a = 0 When you xor a number with another number, a^b, you get an intermediate value c that can be decoded back into either a or b by xor-ing with its opposite number. c^a = b c^b = a Now the swap: First a^b , we'll call it c. Then c^(b = a). This is an assignment statement that reassigns b to a and then has a final value of a. It is equivalent to: b = a; //b is now a c^(a) Expanding c, which encodes the original b, (a^b)^(a) = a^b^a = b^a^a = b^0 = b And that b gets assigned to a. a = b //a is now b Swapped!
3rd Apr 2022, 4:59 AM
Brian
Brian - avatar
+ 1
-- or (a,b) = (b,a);
2nd Apr 2022, 12:41 PM
SoloProg
SoloProg - avatar
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SoloProg Thanks yes it can be done with a tuple but I need to understand how it is swapping the both values
2nd Apr 2022, 12:47 PM
Mahad Ahmed
Mahad Ahmed - avatar
+ 1
Brian Thank you so much. Very well explained and easy to understood answer. Thanks 😊
3rd Apr 2022, 8:30 AM
Mahad Ahmed
Mahad Ahmed - avatar