Programming Structures

1. Control Flow

Python includes basic control flow structures such as conditionals and loops.

1.1 Conditional Statements

Conditional statements control the flow of execution based on conditions.

if-else
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x = 10
if x > 5:
print("x is greater than 5")
elif x == 5:
print("x is equal to 5")
else:
print("x is less than 5")
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Exercise ☕📝

Only sword or arrow can defeat the beast.

Conditional Exercise
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import random

# Hero classes and their actions
heroes = ["Knight 🏰", "Archer 🏹"]sword
actions = {
"Knight 🏰": ["sword", "shield", "lance"],
"Archer 🏹": ["arrow", "trap", "dodge"],
}

# Assign a random hero
hero = random.choice(heroes)

# Assign a random action
action = random.choice(______)

# Print adventure
print(f"You are a {hero}!")
print("A wild beast attacks! 🐺")
print(f"You use {action.upper()}!")

# Determine fate
# Remember, only "sword" or "arrow" can defeat the beast.
if ______ in [______, ______]:
print("The beast is defeated! 🎉")
______:
print("You are overwhelmed. Game over. 💀")
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1.2 Loops

Loops are used to iterate over a sequence of items.

1.2.1 For Loop

For Loop
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for i in range(5):
print(i) # Output: 0, 1, 2, 3, 4
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1.2.2 While Loop

While Loop
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count = 0
while count < 5:
print(count)
count += 1
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Exercise ☕📝

Write a program that prints the first 10 numbers in the Fibonacci sequence. Recall that the Fibonacci sequence starts with 0 and 1, and each subsequent number is the sum of the two preceding numbers. Therefore, the first 10 numbers in the Fibonacci sequence are 0 1 1 2 3 5 8 13 21 34.

Loop Exercise
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# Print the first 10 numbers in the Fibonacci sequence.
a, b = 0, 1
for _ in range(10):
print(a, end=" ")
# there is oneliner here but let's do it in 3 steps first
# 1. store a in temp
temp = ______

# 2. update a to b
a = ______

# 3. update b to ???
b = ______

# Once you get the 3-step approach correct, try to see if you
# can replace the above 3 steps with a single line of code.
# Hint: a, b = ______, ______
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2 Functions

Functions are reusable blocks of code that perform a specific task. We write functions to avoid repetition and improve code readability.

Function
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def greet(name):
return f"Hello, {name}!"

print(greet("Alice")) # Output: Hello, Alice!
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Exercise ☕📝

Write a function cal_interest(principal, rate, years) that takes in the principal amount, annual interest rate, and number of years, and returns the total amount of interest. Assume annual compounding.

Function Exercise
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def cal_interest(______, ______, years):
# Calculate the total amount of interest
interest = ______
return interest
print(cal_interest(1000, 0.05, 2)) # Output: 102.5
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3 Exception Handling

Exception handling ensures robust code execution.

Exception Handling
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try:
result = 10 / 0
except ZeroDivisionError:
print("Cannot divide by zero")
finally:
print("Execution completed")
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