Overview of Arrays

Introduction

• Presenter: Love Bubbar, Channel: Code Help
• Lecture: 9
• Topics: Basics of Arrays, Operations, Functions with Arrays

Basics of Arrays

• Definition: Array is a data structure that can hold multiple elements of the same data type.
• Why Arrays: Simplifies handling multiple data items of the same type, especially useful when dealing with large datasets.
• Example: Finding the largest value among 10,000 integers becomes manageable with arrays.

Use Cases for Arrays

• Store similar data types ( integer, character, custom types).
• Use cases:
  • Finding maximum/minimum values.
  • Simplifying code complexity for large datasets.

Characteristics of Arrays

• Contiguous Memory Allocation: Arrays store elements in contiguous memory locations.
• Indexing:
  • Access elements using an index starting from 0.
  • Example: int v[5] with addresses: 100, 104, 108, 112, 116.
• Operations:
  • Declaration: int arr[10].
  • Initialization: int arr[3] = {5, 7, 11}.
  • Accessing: arr[0], arr[1],..., arr[n-1].

Practical Examples

• Max and Min Values: Finding the largest and smallest element in an array.
• Initialization:
  • Full Initialization: int arr[3] = {5, 7, 11}.
  • Partial Initialization: int arr[10] = {0} initializes all elements to 0.

Arrays and Functions

• Passing Arrays to Functions:
  • Arrays passed by reference, thus actual array gets modified.
  • Example: Update function to modify array elements.
  • Always pass the size of the array to handle array bounds properly.

Key Questions & Exercises

• Examples:
  • Find max/min in an array.
  • Reverse an array: Involves swapping elements from start and end towards the middle.

Future Topics (Teaser for Next Lecture)

1. Swapping alternate elements.
2. Finding unique elements in an array.
3. Identifying duplicate elements (important for interviews).
4. Finding intersection of two arrays.
5. Pair sum and triplet sum problems.
6. Sorting an array of 0s and 1s.

Closing Remarks

• Importance of understanding arrays for data structures and problem solving.
• Encouragement to engage with the material and subsequent lectures.