for loop - range (one argument)

Objective
After working through this lesson, you’ll be able to
Write Python code using the for loop using the range function with one argument.
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Introductory Problem
You worked on while loop menu code previously.  Run the code below and make sure you understand how it works. 
menu.py
done = False
while not done:
    print("Menu")
    print("S - Start")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "S":
        print("Start")
    elif choice == "Q":
        print("Exiting Menu!")
        done = True
done is a Boolean variable and True is the sentinel value.
Add code for the Intro menu item when the user selects I.  
Using a while loop, print your name 5 times.  
intro.py
done = False
while not done:
    print("Menu")
    print("I - Intro")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "I":
        print("Introductory Problem")
        x = 0
        name = input("What's your name? ")
        while x < 5:
            print(name)
    elif choice == "Q":
        print("Exiting Menu!")
        done = True
for loop
Previously, you used while loops to iterate over a range of integer values.  Now you will use a for loop with the range function with one argument.
Programmers usexorias a stepper variable.
Examples
Example 1
Add a Menu Item E1 - Example 1
Using a for loop, print your name 5 times.
example1.py
done = False
while not done:
    print("Menu")
    print("I - Intro")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "I":
        print("Introductory Problem")
        x = 0
        name = input("What's your name? ")
        while x < 5:
            print(name)
    elif choice == "Q":
        print("Exiting Menu!")
        done = True
    elif choice == "E1":
        print("Example 1")
        name = input("What is your name? ")
        for i in range(5):
            print(name)
Example 2
Add a Menu Item E2 - Example 2
Using a for loop, print numbers from 0 to 4.
example2.py
done = False
while not done:
    print("Menu")
    print("S - Start")
    print("E2 - Example 2")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "S":
        print("Starting Game!")
    elif choice == "Q":
        print("Exiting Menu!")
        done = True
    elif choice == "E2":
        print("Example 2")
        for i in range(5):
            print(i)
Example 3
Add a Menu Item E3 - Example 3
Using a for loop, ask the user for 3 numbers.  Print the sum of numbers.
Initialize the variable sum to 0.
example3.py
done = False
while not done:
    print("Menu")
    print("S - Start")
    print("E3 - Example 3")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "S":
        print("Starting Game!")
    elif choice == "Q":
        print("Exiting Menu!")
        done = True
    elif choice == "E3":
        print("Example 3")
        sum = 0
        for i in range(3):
            num = int(input("Number: "))
            sum = sum + num
        print(sum)
Example 4
Add a Menu Item E4 - Example 4
Using a for loop, create the table to show the numbers 0 to 10 and their squares.  Create a header:
print("Number\tSquared")
example4.py
done = False
while not done:
    print("Menu")
    print("S - Start")
    print("E4 - Example 4")
    print("Q - Quit")
    choice = input("Choice: ")
    if choice == "S":
        print("Starting Game!")
    elif choice == "Q":
        print("Exiting Menu!")
        done = True
    elif choice == "E4":
        print("Number\tSquared")
        for i in range(11):
            print(i,"\t",i**2)
Conclusion
In your own words, what is a for loop?
What are the differences between a while loop and a for loop.
Problems
Examples
Last modified 3yr ago