There come situations in real life when we need to make some decisions and based on these decisions, we decide what should we do next. Similar situations arise in programming also where we need to make some decisions and based on these decisions we will execute the next block of code. This is done with the help of decision-making statements in Python.
Example:
# Python program to demonstrate# decision making i = 20; if (i < 15): print ("i is smaller than 15") print ("i'm in if Block") else: print ("i is greater than 15") print ("i'm in else Block") print ("i'm not in if and not in else Block") |
Output:
i is greater than 15 i'm in else Block i'm not in if and not in else Block
Nested-if Statement
We can have an if…elif…else statement inside another if…elif…else statement. This is called nesting in computer programming. Any number of these statements can be nested inside one another. Indentation is the only way to figure out the level of nesting. This can get confusing, so it must be avoided if we can.
Syntax:
if (condition1):
# Executes when condition1 is true
if (condition2):
# Executes when condition2 is true
# if Block is end here
# if Block is end here
FlowChart
Example 1:
# Python program to demonstrate# nested if statement num = 15if num >= 0: if num == 0: print("Zero") else: print("Positive number")else: print("Negative number") |
Output:
Positive number
Example 2:
# Python program to demonstrate# nested if statement i = 13 if (i == 13): # First if statement if (i < 15): print ("i is smaller than 15") # Nested - if statement # Will only be executed if statement above # it is true if (i < 12): print ("i is smaller than 12 too") else: print ("i is greater than 12 and smaller than 15") |
Output:
i is smaller than 15 i is greater than 12 and smaller than 15
