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         INTRODUCTION TO HIGH-LEVEL PROGRAMMING (C++)
         PRACTICAL LAB SESSION 6: Arrays
         State University of Zanzibar (SUZA)
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OBJECTIVES:
- Declare and initialize arrays
- Access and modify array elements
- Pass arrays to functions
- Solve problems using single and multi-dimensional arrays

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PART A: BASIC ARRAY OPERATIONS
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1. Array Input/Output:
   Declare an array of 10 integers. Read values from user and display them.

2. Sum and Average:
   Read 10 numbers into an array. Calculate and display the sum and average.

3. Find Maximum and Minimum:
   Read N numbers into an array. Find and display the largest and smallest
   values and their positions (indices).
   Test: [3, 7, 1, 9, 4] -> Max: 9 at index 3, Min: 1 at index 2

4. Count Occurrences:
   Read N numbers into an array. Ask user for a value to search.
   Count and display how many times it appears.
   Test: [1, 3, 5, 3, 7, 3] search for 3 -> Count: 3

5. Reverse Array:
   Read N numbers into an array. Reverse the array in-place (no second array).
   Display before and after.
   Test: [1, 2, 3, 4, 5] -> [5, 4, 3, 2, 1]


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PART B: SEARCHING & SORTING
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6. Linear Search:
   Write a function int linearSearch(int arr[], int size, int key);
   Returns index if found, -1 if not found.
   Test: [10, 20, 30, 40, 50], key=30 -> Found at index 2

7. Bubble Sort:
   Write a function void bubbleSort(int arr[], int size);
   Sort array in ascending order. Display array after each pass.
   Test: [64, 34, 25, 12, 22, 11, 90]

8. Selection Sort:
   Write a function void selectionSort(int arr[], int size);
   Test with same array as above.

9. Binary Search (on sorted array):
   Write a function int binarySearch(int arr[], int size, int key);
   First sort the array, then search.
   Test: [2, 5, 8, 12, 16, 23, 38, 56, 72, 91], key=23


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PART C: ARRAY PROBLEMS
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10. Remove Duplicates:
    Read N numbers. Display only unique values (remove duplicates).
    Test: [1, 2, 2, 3, 4, 4, 5] -> [1, 2, 3, 4, 5]

11. Merge Two Sorted Arrays:
    Read two sorted arrays. Merge them into a single sorted array.
    Test: [1, 3, 5] + [2, 4, 6] -> [1, 2, 3, 4, 5, 6]

12. Student Grades Table (2D Array):
    Create a 5x3 array for 5 students and 3 subjects.
    Calculate and display:
    - Each student's average
    - Each subject's average
    - Highest score overall

13. Matrix Addition:
    Read two 3x3 matrices. Display their sum.

14. Matrix Multiplication:
    Read two matrices (MxN and NxP). Calculate and display their product.


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PART D: EXTRA PRACTICE (LeetCode / HackerRank Style)
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15. [Easy] Running Sum
    Given array nums, return array where result[i] = sum of nums[0..i].
    Test: [1,2,3,4] -> [1,3,6,10]
    LeetCode 1480

16. [Easy] Contains Duplicate
    Check if any value appears at least twice in the array.
    Test: [1,2,3,1] -> true | [1,2,3,4] -> false
    LeetCode 217

17. [Easy] Single Number
    Every element appears twice except one. Find it.
    Test: [2,2,1] -> 1 | [4,1,2,1,2] -> 4
    Hint: XOR all elements. LeetCode 136

18. [Easy] Move Zeroes
    Move all 0's to the end while maintaining relative order of non-zero.
    Test: [0,1,0,3,12] -> [1,3,12,0,0]
    LeetCode 283

19. [Easy] Plus One
    Given a number represented as array of digits, add one.
    Test: [1,2,3] -> [1,2,4] | [9,9,9] -> [1,0,0,0]
    LeetCode 66

20. [Medium] Two Sum
    Find two numbers in array that add to target. Return their indices.
    Test: [2,7,11,15] target=9 -> [0,1] (because 2+7=9)
    LeetCode 1

21. [Medium] Rotate Array
    Rotate array to the right by k steps.
    Test: [1,2,3,4,5,6,7] k=3 -> [5,6,7,1,2,3,4]
    LeetCode 189

22. [Medium] Missing Number
    Array contains n distinct numbers from 0 to n. Find the missing one.
    Test: [3,0,1] -> 2 | [0,1] -> 2
    Hint: Sum formula n*(n+1)/2. LeetCode 268

23. [HackerRank] Arrays - Left Rotation
    Rotate array left by d positions.
    Link: hackerrank.com/challenges/ctci-array-left-rotation
    Test: [1,2,3,4,5] d=2 -> [3,4,5,1,2]

24. [HackerRank] 2D Array - DS (Hourglass Sum)
    Find the maximum hourglass sum in a 6x6 2D array.
    Link: hackerrank.com/challenges/2d-array

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