Swap Two Numbers
Take two numbers as input and swap them and print the swapped values.

Input Format:

The first line of input contains a single integer 't', representing the total number of test cases. The second line of input contains two integers 'a' and 'b', representing the second number.

Output Format:

The first line of output prints the swapped value of 'a' and 'b'.

Note:

You do not need to print anything, it has already been taken care of. Just implement the given function.

Constraints:

1

Question

Swap Two Numbers

Take two numbers as input and swap them and print the swapped values.

Input Format:

The first line of input contains a single integer 't', representing the total number of test cases.

The second line of input contains two integers 'a' and 'b', representing the second number.

Output Format:

The first line of output prints the swapped value of 'a' and 'b'.

Note:

You do not need to print anything, it has already been taken care of. Just implement the given function.

Constraints:

1 <= 'T' <= 10^2
-10^5 <= 'a', 'b' <= 10 ^ 5

Time Limit: 1 sec

Accepted Answer

Approach 1 (Using Destructruring Assignment) : This method was specific only for JS and the interviewer was preety
impressed when I used it .

Destructuring assignment (a feature of ES2015) lets you extract items of an array into variables. It works with any
data type: numbers, strings, booleans, objects.

Code :

let a = 1;
let b = 2;
[a, b] = [b, a];
a; // => 2
b; // => 1

[a, b] = [b, a] is the destructuring assignment that swaps the variables a and b.

Approach 2 (Normal Method - Using a temporary variable - Not recommended in interviews though) :

Code :

let a = 1;
let b = 2;
let temp;
temp = a;
a = b;
b = temp;
a; // => 2
b; // => 1

temp is the temporary variable.
At the first step, temp is assigned with the value of a. Then a variable is assigned with the value of b. Finally, the
variable b is assigned with the value of temp (having the initial value of a).

Approach 3 (Without using temporary variable - Using Addition and Difference) :

Code :

let a = 1;
let b = 2;
a = a + b;
b = a - b;
a = a - b;
a; // => 2
b; // => 1

Initially, a is 1 and b is 2. Let's see how the 3 statements perform the swapping:

a = a + b assigns to a the value 1 + 2.
b = a - b assigns to b the value 1 + 2 - 2 = 1 (b is now 1).
a = a - b assigns to a the value 1 + 2 - 1 = 2 (a is now 2).

Finally, a is 2 and b is 1. The swapping of a and b has been performed.

Accepted Answer

Swapping using a temporary variable

Take input in two integer datatype variables, a and b. Create a temporary variable temp and initialize it equal to a. Now make a equal to b, and finally make b equal to temp. Print a and b.

Space Complexity: O(1)Explanation:

O(1),

The Space Complexity is O(1).

Time Complexity: O(1)Explanation:

O(1),

The Time Complexity is O(1).

Accepted Answer

Using arithmetic operation

We can swap values of two variables by using a third variable and instead of that, we can use the arithmetic operation to do it without an extra variable.
The idea is to store the sum of two variables in the first variable. Now if we assign the sum(which is 1st variable) - 2nd variable in the 2nd variable then the value in the 2nd variable will be equal to the 1st variable.
Again assign the first variable equal to the sum(first variable) - 2nd variable(which has a value equal to 1st variable) so 1st variable will now have a value equal to 2nd variable.

Space Complexity: O(1)Explanation:

O(1),

The Space Complexity is O(1).

Time Complexity: O(1)Explanation:

O(1),

The Time Complexity is O(1).

Take two numbers as input and swap them and print the swapped values.

Input Format:

Output Format:

Note:

Constraints:

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