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Challenge 4.2

Count dots on 5 black and white cards (using a loop)

Challenge Level: Growing experience

Requirement:

Write a program that asks the end user to enter 5 black and white cards representing bits ('B' for black and 'W' for white which are entered one at a time) and displays the total number of dots as the output. Use a loop for this challenge, so it could be changed to work for a different number of cards.

Hints
  • Make a variable called total_number_of_dots and set its value to 0.
  • Make another variable called number_of_dots and set its value to 16.
  • Add the value of number_of_dots to the value of total_number_of_dots every time the end user enters ‘W’ as the input. Repeat this 5 times dividing the value of number_of_dots by 2 each time and convert the result to an integer using int().
  • Display the total_number_of_dots as the output.
  • Use a for loop to repeat this five times
Programming Reminders
# Print a string directly
print("Hello World!")

# Print a variable
print(my_var)

Variables

# Set a variable as a string
fruit_name = "Apple"

# Set a variable as an integer 
pieces_of_fruit = 7

# Set a variable from a calculation
cost_of_fruit = pieces_of_fruit * cost_per_item

# Add one to a value
pieces_of_fruit += 1

Conditionals

# Find out the discount on fruit
if pieces_of_fruit > 100:
   print("Bulk discount applies")
elif pieces_of_fruit > 5:
   print("Discount applies")
else:
   print("No discount")

For loops

# Print numbers 0-9 - remember Python starts counting from 0 
for num in range(10):
    print(num)

While loops

# Print numbers 0-9 using a while loop and a variable
num = 0
while num < 10:
    print(num)

    # Increment the variable by one.
    # It will prevent an infinite loop!
    num += 1 

Lists

# Create a list of fruit 
fruit = ["Apple", "Banana", "Orange", "Pear"]

Functions

# Create a function which prints a greeting
def greeting(name):
    print("Hello " + name)

# Call the function
greeting("Spiderman")

Enter your code in the editor below

Your results will be displayed here

Input Expected output Received output Status
B
W
W
B
W
13

                
Not yet run ?
B
B
B
B
B
0

                
Not yet run ?
W
W
W
W
W
31

                
Not yet run ?