Python Control Statements

Control statements are used to control the flow of execution depending upon the specified condition/logic.

1. if- Statement

   An if statement is a programming conditional statement that, if the condition is true, it executes the block of code inside of it.

   

   books = 2  
   if (books == 2) :
      print(" You have")  
      print("Two books")  
   print("Outside of if statement") 

   In the above code, we are checking if books is equal to 2, then execute the given code.

2. if-else statement

   The if-else statement executes some code if the test expression is true (non-zero) and some other code if the test expression is false.

   

   a=10  
   if a<100:   
         print('less than 100')  
   else:  
         print('more than equal 100')  

   In the above code, we are checking if a is less than 100, else will print "more than equal 100'.

3. Nested If-Else Statement

   The nested if ... else statement allows you to check for multiple test expressions and executes different codes for more than two conditions.

   num = float(input("enter a number:"))  
   if num >=0:  
        if num==0:  
            print("zero")  
   else:  
        print("Negative number")  

   In the above code, we are first checking if num is greater than or equal to 0 and then if it is zero if both the conditions are met, "zero" is printed, otherwise "Negative number".