Converting string input to numbers using int() and float()
Displaying user input with print()
The input() Function
The input() function pauses the program and waits for the user to type something.
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name =input("Enter your name: ")
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print("Hello", name)
The input() Function
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name =input("Enter your name: ")
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print("Hello", name)
Sample
Enter your name: Alex [Enter]
Hello Alex
All Input is a String
By default, input() always returns a string value, even if the user types a number.
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age =input("Enter your age: ")
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print("You are", age *12,"months old.")
Note
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Enter your age: 35 [enter]
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You are 353535353535353535353535 months old.
Issues with Strings and Arithmetic
Because strings aren't treated as numbers in Python, you must
convert them before doing arithmetic; otherwise, your calculations
may not work as expected.
"3" + "3" # 33
2 * "3" + "3" # 333
Converting Input to Numbers
To perform arithmetic with input, you must convert it to a number using int() or float().
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height =float(input("Enter your height in meters: "))
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print("Double your height is", height *2)
Engineering Example
Combine integer and floating-point input for calculations.
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count =int(input("Enter the number of bolts needed: "))
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cost =float(input("Enter cost per bolt ($): "))
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total = count * cost
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print(f"Total cost = ${total}")
Sample
Enter the number of bolts needed: 5
Enter cost per bolt ($): 0.75
Total cost = $3.75
int() vs. float()
Use int() when you need a whole number (student ID, age, number of people,
etc.).
Use float() when you need a decimal number (dollar amount, weight, GPA, etc.).
Key Terms
input() Function
Pauses the program to accept input from the user as text (string).
Type Conversion
The process of changing a value's data type using functions like int() or float().
int()
Converts a string into an integer (whole number).
float()
Converts a string into a floating-point (decimal) number.
'F' → Fullscreen
Objectives
Use input() to gather user input.
Store and display input values using variables.
Convert string input into numeric data types with int() and float().
Perform arithmetic using user-provided values.
Activity Tasks
Create a new project named 1-2-input.py.
Complete each task individually.
Task 1: Getting User Input
1-2-input.py
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# Activity 1.2 - Task 1
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# Getting user input
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name =input("Enter your name: ")
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print("Welcome,", name)
Task 2: Input Strings and Numbers
1-2-input.py
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# Activity 1.2 - Task 1
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# Getting user input
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name =input("Enter your name: ")
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print("Welcome,", name)
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# Task 2 - Input Strings and Numbers
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tool =input("Enter the tool name: ")
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price =input("Enter the price: ")
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print("The", tool,"costs $", price)
Task 3: Convert Numeric Input
1-2-input.py
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# Activity 1.2 - Task 1
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# Getting user input
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name =input("Enter your name: ")
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print("Welcome,", name)
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# Task 2 - Input Strings and Numbers
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tool =input("Enter the tool name: ")
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price =input("Enter the price: ")
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print("The", tool,"costs $", price)
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# Task 3 - Convert numeric input
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radius =float(input("Enter radius of the circle (cm): "))
Use 
Create a new project named 1-2-input.py.