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         INTRODUCTION TO HIGH-LEVEL PROGRAMMING (C++)
         PRACTICAL LAB SESSION 5: Functions & Procedures
         State University of Zanzibar (SUZA)
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OBJECTIVES:
- Define and call functions with parameters and return values
- Understand pass by value vs pass by reference
- Use function prototypes
- Apply functions to organize code

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PART A: BASIC FUNCTIONS (From Course Materials)
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1. Write a function that takes two integers and returns their sum.
   int add(int a, int b);
   Test: add(3, 5) = 8 | add(-2, 7) = 5

2. Write a function that takes an integer and returns true if it's even.
   bool isEven(int n);
   Test: isEven(4) = true | isEven(7) = false

3. Write a function that takes a float radius and returns the area of a circle.
   float circleArea(float radius);
   Test: circleArea(5) = 78.5398

4. Write a function that takes three quiz scores and returns the average.
   float average(float q1, float q2, float q3);

5. Write a void function that takes an integer n and prints a line of n stars.
   void printStars(int n);
   Test: printStars(5) prints "*****"

6. Write a function that calculates and returns the factorial of n.
   long long factorial(int n);
   Test: factorial(5) = 120 | factorial(0) = 1


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PART B: PASS BY REFERENCE
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7. Swap Function:
   Write a function that swaps two integers using pass by reference.
   void swap(int &a, int &b);
   Demonstrate it works by printing before and after swap.

8. Min and Max:
   Write a function that takes an array of integers and its size, and returns
   the minimum and maximum using reference parameters.
   void findMinMax(int arr[], int size, int &min, int &max);

9. Grade Calculator Function:
   Write a function that takes three scores (by value) and returns the grade
   (by reference) and average (by reference).
   void calculateGrade(int q, int m, int f, float &avg, char &grade);


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PART C: FUNCTION OVERLOADING & DEFAULT PARAMETERS
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10. Overloaded Area Functions:
    Write three overloaded functions named "area":
    - float area(float radius);           // Circle
    - float area(float length, float width);  // Rectangle
    - float area(float base, float height, bool isTriangle);  // Triangle

11. Power Function with Default:
    Write a function with default exponent of 2:
    double power(double base, int exp = 2);
    Test: power(3) = 9 | power(2, 10) = 1024

12. Temperature Converter:
    Write two overloaded functions:
    float convert(float celsius);          // Celsius to Fahrenheit
    float convert(float temp, char from);  // 'C' or 'F' conversion


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PART D: FUNCTIONS WITH LOOPS
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13. Prime Check Function:
    bool isPrime(int n);
    Use this in main() to print all primes from 1 to 100.

14. GCD Function (Recursive):
    int gcd(int a, int b);
    Use Euclid's algorithm: gcd(a, b) = gcd(b, a % b), base case: gcd(a, 0) = a
    Test: gcd(48, 18) = 6 | gcd(100, 75) = 25

15. Fibonacci Function (Recursive):
    int fibonacci(int n);
    Return the nth Fibonacci number.
    Test: fibonacci(0)=0, fibonacci(1)=1, fibonacci(10)=55

16. Menu-Driven Calculator:
    Create a calculator with functions for add, subtract, multiply, divide.
    Use a menu loop. Each operation should be its own function.


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PART E: EXTRA PRACTICE (LeetCode / HackerRank Style)
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17. [Easy] Absolute Value Function
    Write int myAbs(int n) that returns absolute value without using abs().

18. [Easy] Max of Three
    Write int maxOfThree(int a, int b, int c) using only comparisons.
    Test: maxOfThree(3, 7, 5) = 7

19. [Easy] Count Vowels
    Write int countVowels(string str) that counts vowels in a string.
    Test: "Hello World" -> 3

20. [Medium] Power (Recursive)
    Write double myPow(double x, int n) using recursion.
    Handle negative exponents: x^(-n) = 1 / x^n
    Test: myPow(2, 10) = 1024 | myPow(2, -2) = 0.25

21. [Medium] Digital Root
    Repeatedly sum digits until a single digit remains.
    Write int digitalRoot(int n);
    Test: 9875 -> 9+8+7+5=29 -> 2+9=11 -> 1+1=2, return 2

22. [Medium] Check Palindrome String
    Write bool isPalindrome(string str);
    Test: "madam" -> true | "hello" -> false | "racecar" -> true

23. [HackerRank] Mini-Max Sum
    Given five positive integers, find the min and max sums of exactly four.
    Link: hackerrank.com/challenges/mini-max-sum
    Test: [1,2,3,4,5] -> Min sum: 10, Max sum: 14

24. [LeetCode 231] Power of Two
    Write bool isPowerOfTwo(int n);
    Test: 16 -> true | 18 -> false | 1 -> true | 0 -> false

25. [LeetCode 326] Power of Three
    Write bool isPowerOfThree(int n);
    Test: 27 -> true | 45 -> false | 1 -> true

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