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Challenges

Challenge 2.1

# Display number of dots for a given number of cards

Challenge Level: Growing experience

## Requirement:

Write a program to display numbers 1, 2, 4, 8,... (one at a time) for a given number of cards entered as the input.

Hints
• Make a variable called number_of_cards to store the number of cards to display entered by the end user as the input (e.g. 5) and a variable called number of dots to store the number of dots (e.g. 1, 2, 4, 8, 16) where each number is calculated by multiplying the previous number by 2.

• In this challenge, use the input() function to receive input from the user. Place text inside the brackets of input with your question. The user input will be stored whichever variable you assign it to. Set the value of variable number_of_cards to the input you received. Use a for loop, repeating the blocks inside (displaying the number of dots) number_of_cards 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
5
1
2
4
8
16

Not yet run ?
8
1
2
4
8
16
32
64
128

Not yet run ?
1
1

Not yet run ?