how to swap two variables

how to swap two variables 



This is common question to swap the values of two variables in each of the programing language and there are different ways to do it ,python have 4 ways to swap the variables .

1.Using Temporary Variable

2.Using two variable

3.Using EX-or Gate

4.Swap using two variable and code should be written in single line


Python  : 
                  

1.Using Temporary Variable : 

                                                    In this method we have to define three variables one temporary variable and two another variables whos values we want to swap
 a= 10
 b=20 
 //let temp be the Temporary Variable 
temp =a

a=b

b=temp

so by using above code we can swap the values of variable 
Now if we print a and b
a=20
b=10


                                                                       



2.Using Two variables  :

                                                We can swap the values of two variables without using the  temporary
variables ,this method is also called as special formula method to swap the values ,the formula/syntax is 
 a = a + b

 b = a - b

 a = a - b
 to understand this formula consider one example where a=5,b=10.
 at first step 

                       a = a + b /  a =15
                          

                       b = a - b / b = 5

                       a = a - b/ a=10 

Now if we print a and b values get swap successfully  ,This method is vary important and easy, as because it not required third variables,  question ask vary often in Interviews that swap the values only with two variable



3.Using EX-or Gate ;
Here is another method to swap the values of Variables with the help of Ex-or gate and to understand this method we must be familiar  with truth table of Ex-or gate here is table


Input       Input     Output 
 0               0            0
 1               0            1
 0               1            1
 1               1            0


 a =  a ^ b

 b = a ^ b

 a =  a ^ b

 to understand this formula consider one example where a=5,b=10

 a =  a ^ b // a = 1111 

 b = a ^ b  //b=0101       …... From Above table 
 a =  a ^ b //a=1010


 Now if we Print value of a and b the values get swap
a = 1010  ( Decimal 10)
b = 0101 (Decimal 5)
so in this way by using Ex-or gate we can swap the values of two variables



4.Swap using two variable and code should be written in single line:
 Here are two conditions that we have to swap the values with two variables and the code must be written on single line  to execute this there is syntax In python
a , b = b , a 
let a =5, b=10
a , b = b , a 
 Now if we Print a and b the values get swap ,to understand how it actually execute simply debug the code




So These are the 4 ways to swap the variables in Python that we have discuss above




Thank u😊