Python_Day 9

Python Day 9_Beginner – Dictionaries, nesting and the secret auction

Dictionaries
To create a dictionary the syntax is {key: Value} which is the content. For example:
{“Bug”: “An error in a program that prevents the program from running as expected.”}
If you want to add more contents to the dictionary, you would add a comma at the end and continue.
{
“Bug”: “An error in a program that prevents the program from running as expected.”,
“Function”: “A piece of code that you can easily call over and over again.”,
“loop”: “ “,
}

To receive information from a dictionary list, you have to provide a key instead of a number in a list such as programming_dictionary[“Bug”] -> outputs the value
You can also add new items to dictionary -> programming_dictionary[“loop”] = “Info”

You can also create an empty dictionary from scratch:
empty_dictionary = {}

You can also wipe an existing dictionary
programming_dictionary = {} -> clears all contents

To loop through a dictionary:
for key in progamming_dictionary:
   print(key)
   print(programming_dictionary[key]) -> prints the key and value in order

#caution. If you do not set the parameters correctly it will only show either the key or value.
for thing in programming_dictionary:
           print(thing) -> bug, function, loop

 

Grading Program – Coding exercise
You have access to a database of student_scores in the format of a dictionary. The keys in student_scores are the names of the students and the values are their exam scores.

Write a program that converts their scores to grades. By the end of your program, you should have a new dictionary called student_grades that should contain student names for keys and their grades for values.

student_scores = {

  "Harry": 81,

  "Ron": 78,

  "Hermione": 99,

  "Draco": 74,

  "Neville": 62,

}

# 🚨 Don't change the code above 👆

# TODO-1: Create an empty dictionary called student_grades.

student_grades = {}

 

# TODO-2: Write your code below to add the grades to student_grades.👇

for name, score in student_scores.items():

  if score > 90:

    student_grades[name] = "Outstanding"

  elif 81 <= score <= 90:

    student_grades[name] = "Exceeds Expectations"

  elif 71 <= score <= 80:

    student_grades[name] = "Acceptable"

  else:

    student_grades[name] = "Fail"

 

# 🚨 Don't change the code below 👇

print(student_grades)

Nesting
Putting one dictionary into another. Similar to the following example below:
{
 key: [list],
 key2:{dict},
}

#Nesting a list in a dictionary
Travel_log = {
 “France”: [“Paris”, “Lille”, “Dijon”]
 “Germany”: [“Berlin”, “Hamburg”, “Stuttgart”],
}

#Nesting dictionary in a dictionary
travel_log = {

    "France": {"cities_visited": ["Paris", "Lille", "Dijon"], "total_visits": 12},

    "Germany": ["Berlin", "Hamburg", "Stuttgart"],

}

#Nesting dictionary in a list

travel_log = [

    {

     "country": "Thailand",

     "cities_visited": ["Bangkok", "Pattaya", "Ko-tok", "Ayuttaya", "Phuket"],

     "total_visits": 25

    },

    {

     "country": "Vietnam",

     "cities_visited": ["Hochimihn", "Hanoi"],

     "total_visits": 1

    },

]

Dictionary in a list – Coding Exercise
You are going to write a program that adds to a travel_log. You can see a travel_log which is a List that contains 2 Dictionaries. Your job is to create a function that can add new countries to this list.

country = input() # Add country name

visits = int(input()) # Number of visits

list_of_cities = eval(input()) # create list from formatted string

 

travel_log = [

  {

    "country": "France",

    "visits": 12,

    "cities": ["Paris", "Lille", "Dijon"]

  },

  {

    "country": "Germany",

    "visits": 5,

    "cities": ["Berlin", "Hamburg", "Stuttgart"]

  },

]

# Do NOT change the code above 👆

 

# TODO: Write the function that will allow new countries

# to be added to the travel_log.

def add_new_country(country, visits, list_of_cities):

  new_country_entry = {

    "country": country,

    "visits": visits,

    "cities": list_of_cities

  }

  travel_log.append(new_country_entry)

 

# Do not change the code below 👇

add_new_country(country, visits, list_of_cities)

print(f"I've been to {travel_log[2]['country']} {travel_log[2]['visits']} times.")

print(f"My favourite city was {travel_log[2]['cities'][0]}.")

output:
I've been to Brazil 2 times.

My favourite city was Sao Paulo.

Alternative code
def add_new_country(name, times_visited, cities_visited):
           new_country = {}
           new_coutnry[“country”] = name
           new_country[“visits”] = times_visites
           new_country[“cities”] = cities_visited

           Travel_log.append(new_country)

Project 9_Secret Auction

name = input("What is your name?: ") #name of the bidder

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

 

secret_auction = []

def bidding(name, bid):

    new_bidder = {

        "name": name,

        "bidder": bid,

    }

    secret_auction.append(new_bidder)

 

while True:

    other_bidders = input("Are there any other bidders? Type 'yes' or 'no'.")

    if other_bidders == "yes":

        print('\n' * 20)

        name = input("What is your name?: ")  # name of the bidder

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

        bidding(name, bid)

    if other_bidders == "no":

        highest_bidder = max(secret_auction, key=lambda x: x['bidder'])

        highest_bid = max(bidder['bidder'] for bidder in secret_auction)

        print(f"The winner is {highest_bidder['name']} with a bid of ${highest_bid}")

        break

 

Alternative code

bids = {
bidding_finished = False

Def find_highest_bidder(bidding_record):

Highest_bid = 0
  for bidder in bidding_record:
    bid_amount = bidding_record[bidder]
    if bid_amount > highest_bid:
     highest_bid = bid_amount
     winner = bidder
  print(f”The winner is {winner} with a bid of ${highest_bid}”)

while not bidding_finished:
  name = input("What is your name?: ")
  price = int(input("What is your bid?: $"))
  bids[name] = price
  should_continue = input(“Are there are other bidders? Type ‘yes or ‘no’.”)
  if should_continue == “no”:
    bidding_finished = True
    find_highest_bidder(bids)
  elif should_continue == “yes”:
    clear() #for replit