The if Statement

Chapter 3

Agenda1. Relational operators: >, <, <=, >=, ==, !=

2. The if-elif-else statement

3. Logical operators: and or not

3.1 The if Statement

Program Output

Indentation: Whitespace Matters!1 tab = 4 spaces

Indentation examples

3.2 The if-else Statement

if-else statement

Program output

if-else statement w boolean

if-else statement w boolean, version 2

3.3 String comparison

Program output

String comparison is case sensitive

Program Output

3.5 Logical Operators

Operator Description

and will return true when both conditions are true.

or will return true when at least one condition is true.

not If the condition is true, not operator will make it false.

Logical and

Program output

Logical or

Program output

Operator not

Program output

3.4 The if-elif-else Statement

Testing a series of conditions

Age:infant, child, teenager, adult. Write a program that asks a user to enter a person’s age. The program should then display a message if the person is an infant, child, teenager or adult.

Solution -where’s the bug?

3.4 Nested if-elif-else statements