Python - Dictionaries and Nesting (Day 9)

This is a 100 Days challenge to learn a new language (Python). 100 Days of Code - The Complete Python Pro Bootcamp 

I will post some notes to motivate myself to finish this challenge.

Dictionaries

Like real life dictionaries, it contains keys (Vocabulary) and its value (Definition) for users to easily access. Reference

Ex:

# Define a dictionary

# The values of a dictionary can be any type

# But the keys must be one of an immutable data type such as string,

# number, or tuples

user_info = {

    "name": "Frank",

    "gender": "Male",

}

Some Basic Usage

Ex:

# Define a dictionary

user_info = {

    "name": "Frank",

    "gender": "Male",

}

# Print dictionary elements

print(user_info)

# Get dictionary element by its key

print(user_info["name"])

# Adding a new item to dictionary

# or edit an existing item in a dictionary

user_info["address"] = "xxx"

print(user_info)

user_info["address"] = "xxxx"

print(user_info)

# Loop through a dictionary

for key in user_info:

    print(user_info[key])

# Checking length

print(len(user_info))

# Empty dictionary/Wipe an existing dictionary

user_info = {}

print(user_info)

Result:

{'name': 'Frank', 'gender': 'Male'} Frank {'name': 'Frank', 'gender': 'Male', 'address': 'xxx'} {'name': 'Frank', 'gender': 'Male', 'address': 'xxxx'} Frank Male xxxx 3 {}

More Complex Case

Ex:

# Nesting a List in a Dictionary

travel_log = {

    "Asia": [

        "Korea",

        "Japan"

    ],

    "North America": [

        "Canada",

        "US"

    ],

}

print(travel_log)

# Nesting a Dictionary in a Dictionary

travel_log = {

    "Asia": {

        "visited": ["Korea", "Japan"],

        "total_visits": 5

    },

    "North America": {

        "visited": ["Canada", "US"],

        "total_visits": 3,

    },

}

print(travel_log)

# Nesting Disctionary inside a List

travel_log = [

    {

        "Area": "Asia",

        "visited": ["Taiwan", "Japan"],

        "total_visits": 5

    },

    {

        "Area": "North America",

        "visited": ["Canada", "US"],

        "total_visits": 3,

    }

]

print(travel_log)

Result:

{

'Asia': ['Korea', 'Japan'],

'North America': ['Canada', 'US']

}

{

'Asia': {

'visited': ['Korea', 'Japan'],

'total_visits': 5

},

'North America': {

'visited': ['Canada', 'US'],

'total_visits': 3

}

}

[

{

'Area': 'Asia',

'visited': ['Taiwan', 'Japan'],

'total_visits': 5

},

{

'Area': 'North America',

'visited': ['Canada', 'US'],

'total_visits': 3

}

]

Challenge - The secret auction game

What is it? Reference

Ex:

# Define a flag to determine the while loop should be stopped or not

game_is_ended = False

# Define a dictionary to store name as a key and the bid as a value

bids = {}

# Define a custom Func to determine the winner (highest bid)

def check_highest_bid():

    max_bid = 0

    winner = ""

    for key in bids:

        if bids[key] > max_bid:

            max_bid = bids[key]

            winner = key

    print(f"The winner is {winner} with a bid of ${max_bid}")

# Loop for the user input

while not game_is_ended:

    # Ask user for the name and their bid

    name = input("What is your name?:")

    bid = int(input("What is your bid?: $"))

    # Add it to the dictionary

    bids[name] = bid

    # Ask for keep continued or not

    should_continue = input("Are there any other bidders? Type 'yes or

'no'.")

    if should_continue == 'no':

        game_is_ended = True

  # Check the result

check_highest_bid()

Result:

What is your name?:Frank What is your bid?: $10

Are there any other bidders? Type 'yes or 'no'.yes

What is your name?:Jake What is your bid?: $20

Are there any other bidders? Type 'yes or 'no'.no The winner is Jake with a bid of $20