Day 14: Introduction to Dictionaries

Task: Explore and manipulate dictionaries to work with key-value pairs.

Description:
A dictionary in Python is a collection of key-value pairs, where each key is unique. Dictionaries are mutable, allowing you to update, add, or remove items dynamically.

In today’s task, you will:

  1. Create dictionaries to store data in key-value pairs.
  2. Access and modify elements using keys.
  3. Use methods to add, remove, and retrieve items.
  4. Perform operations like iterating over keys and values.

1.Creating a dictionary

Define a dictionary with key-value pairs to store related data.

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student_scores = {
    "Alice": 85,
    "Bob": 90,
    "Charlie": 78
}

2.Accessing elements

Retrieve the value associated with a specific key in the dictionary.

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print("Alice's Score:", student_scores["Alice"])  # Output: Alice's Score: 85

3.Adding a new key-value pair

Add a new key and its corresponding value to the dictionary.

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student_scores["Diana"] = 92
print("Updated Dictionary:", student_scores)  # Output: Updated Dictionary: {'Alice': 85, 'Bob': 90, 'Charlie': 78, 'Diana': 92}

4.Modifying an existing value

Update the value of a specific key in the dictionary.

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student_scores["Alice"] = 88
print("Modified Score for Alice:", student_scores["Alice"])  # Output: Modified Score for Alice: 88

5.Removing a key-value pair

Remove a key and its associated value using the pop() method.

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removed_score = student_scores.pop("Charlie")
print("Removed Charlie's Score:", removed_score)  # Output: Removed Charlie's Score: 78
print("Dictionary after removal:", student_scores)  # Output: {'Alice': 88, 'Bob': 90, 'Diana': 92}

6.Iterating through the dictionary

Loop through key-value pairs to process or display the dictionary’s contents.

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for student, score in student_scores.items():
    print(f"{student}: {score}")
    # Output: Alice: 88, Bob: 90, Diana: 92