Home About Me

Python Practice: Conditionals, Lists, and Dictionaries

2026-03-23

Alien colors

A simple check against a green alien awards 5 points.

AlienColor = 'green'
if AlienColor == 'green':
    print("Player gets 5 points.")

Adding an else branch handles other colors, giving 10 points for anything else.

AlienColor = 'green'
if AlienColor == 'green':
    print("Player gets 5 points by shooting this alien.")
else:
    print("Player gets 10 points.")

An elif chain distinguishes green, yellow, and other colors.

AlienColor = 'green'
if AlienColor == 'green':
    print("Player gets 5 points.")
elif AlienColor == 'yellow':
    print("Player gets 10 points.")
else:
    print("Player gets 15 points.")

Life stages

Using a person's age to print a life stage. Two versions are shown.

age = 24
if age < 2:
    print("It's a baby")
elif age >= 2 and age < 4:
    print("It's a child")
elif age >= 4 and age < 13:
    print("It's a tween")
elif age >= 13 and age < 18:
    print("It's a teenager")
elif age >= 18 and age < 65:
    print("It's an adult")
else:
    print("It's an elder")

# alternative solution
age = 24
if age < 2:
    print("It's a baby")
elif 2 <= age < 4:
    print("It's a child")
elif 4 <= age < 13:
    print("It's a tween")
elif 13 <= age < 18:
    print("It's a teenager")
elif 18 <= age < 65:
    print("It's an adult")
else:
    print("It's an elder")

Checking for an empty sequence

Two ways to test whether a list is empty.

a = []
if len(a) == 0:
    print("Empty.")
else:
    print("Not empty.")

# alternative solution
if not a:
    print("Empty.")
else:
    print("Not empty.")

Nested lists

Iterating through a list that contains a string, a tuple, and a nested dictionary.

a = ["str, 12345", ('tunpe', 2) ,{'dict':{'dict': {'dict': 4}}}]
for i in range(len(a)):
    if i == 0:
        print(a[i], end=' ')
    elif i == 1:
        for j in a[i]:
            print(j, end=' ')
    elif i == 2:
        for k1, v1 in a[i].items():
            print(f"key: {k1}, value: {v1}")
            for k2, v2 in v1.items():
                print(f"key: {k2}, value: {v2}")
                for k3, v3 in v2.items():
                    print(f"key: {k3}, value: {v3}", end=' ')
    print()

Sequence packing

Pairing two lists with zip and then building a dictionary with adjusted ages.

name = ['lys', 'wjq', 'hfcj', 'xhz', 'jcg']
age = [104, 504, 1909, 14, 3.14]
info = {k:v + 10 for k, v in zip(name, age)}
for k, v in info.items():
    print(f"Name: {k}, NowAge: {v}")

Related Posts