Binary Decisions
if
and else
statements
if
and else
statements
if (boolean condition):
# if's code block
code here
else:
# else's code block
# end of the conditionals
code continues here
The if’s code block only execute if its boolean condition is True
The else’s code block will execute only when the if’s boolean condition is False
This helps us create two pathways in our code
# Code Example 1
num = 100
if num < 0 and num > 100:
print(num, 'is invalid.')
else:
print(num)
# since the if statement's condition is False we get to execute just the print(num) statement
Output:
100
# Code Example 2
word = 'hello world!'
if 'o' in word:
print('The letter o exists.')
else:
print('The letter o does not exist.')
# examine that the print statement inside the else statement does not execute.
Output:
The letter o exists.
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