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         INTRODUCTION TO HIGH-LEVEL PROGRAMMING (C++)
         PRACTICAL LAB SESSION 3: Control Flow (if, else, switch)
         State University of Zanzibar (SUZA)
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OBJECTIVES:
- Use if, else if, and else statements
- Implement switch-case structures
- Handle input validation and edge cases
- Solve decision-based problems

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PART A: IF-ELSE STATEMENTS (From Course Materials)
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1. Write a program that reads three numbers and prints the largest number.

2. Student Grade Calculator:
   Read three scores (quiz, mid-term, final). Calculate average and assign:
   - Average >= 90% -> Grade A
   - Average >= 70% and < 90% -> Grade B
   - Average >= 50% and < 70% -> Grade C
   - Average < 50% -> Grade F
   Display the grade.

3. Quiz Grade (Switch):
   A professor gives 5-point quizzes: 5=A, 4=B, 3=C, 2=D, 1=F, 0=F.
   Read a quiz score and use a switch statement to display the grade.


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PART B: DECISION STRUCTURES (From Course Materials)
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4. Body Mass Index (BMI) Calculator:
   BMI = weight(kg) / height(m)^2
   Read weight and height, calculate BMI, and classify:
   - BMI < 18.5: Underweight
   - 18.5 <= BMI < 25: Normal weight
   - 25 <= BMI < 30: Overweight
   - BMI >= 30: Obese

5. Leap Year Checker:
   A year is a leap year if:
   - Divisible by 4 AND not divisible by 100, OR
   - Divisible by 400
   Test: 2024 (leap), 1900 (not leap), 2000 (leap), 2023 (not leap)

6. Simple Calculator:
   Read two numbers and an operator (+, -, *, /).
   Use switch to perform the operation.
   Handle division by zero.

7. Triangle Type Checker:
   Read three sides. First check if they form a valid triangle
   (sum of any two sides > third side), then classify:
   - Equilateral (all sides equal)
   - Isosceles (two sides equal)
   - Scalene (no sides equal)

8. Electricity Bill Calculator:
   Read units consumed. Calculate bill:
   - First 100 units: TZS 50 per unit
   - Next 200 units: TZS 75 per unit
   - Above 300 units: TZS 100 per unit
   Add 15% surcharge to total.


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PART C: NESTED DECISIONS & COMPLEX CONDITIONS
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9. Ticket Price System:
   A cinema charges based on age and day:
   - Children (< 12): TZS 5,000
   - Teens (12-17): TZS 8,000
   - Adults (18-59): TZS 12,000
   - Seniors (60+): TZS 6,000
   - Weekend surcharge: +20% for all
   Read age and day (weekday/weekend), display price.

10. Login System:
    Set a username = "admin" and password = "suza2024".
    Ask user to input username and password.
    Give 3 attempts. Display appropriate messages:
    - "Login successful!"
    - "Invalid username or password. X attempts remaining."
    - "Account locked!"

11. Quadratic Equation Solver:
    Read a, b, c for ax^2 + bx + c = 0.
    Calculate discriminant = b^2 - 4ac.
    - If discriminant > 0: two real roots
    - If discriminant == 0: one real root
    - If discriminant < 0: no real roots
    Display the roots using the quadratic formula.


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PART D: EXTRA PRACTICE (LeetCode / HackerRank Style)
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12. [Easy] Positive, Negative, or Zero
    Read a number. Print "Positive", "Negative", or "Zero".

13. [Easy] Vowel or Consonant
    Read a character. Print if it's a vowel or consonant.
    Handle both uppercase and lowercase.
    Test: 'a' -> Vowel | 'B' -> Consonant | 'E' -> Vowel

14. [Easy] Minimum of Three
    Read three numbers and print the minimum WITHOUT using min().

15. [Medium] Day of Week
    Read a number 1-7. Print the day name using switch.
    Handle invalid input (not 1-7).

16. [Medium] Grade Boundaries
    Read a score (0-100) and print the letter grade:
    A+ (97-100), A (93-96), A- (90-92),
    B+ (87-89), B (83-86), B- (80-82),
    C+ (77-79), C (73-76), C- (70-72),
    D (60-69), F (0-59)

17. [Medium] Rock Paper Scissors
    Two players each enter R, P, or S.
    Determine the winner using if-else logic.
    Test: R vs S -> Player 1 wins | P vs P -> Tie

18. [HackerRank] Comparing the Triplets
    Alice and Bob each have 3 scores. For each position, the one with the
    higher score gets 1 point. Print Alice's and Bob's total points.
    Link: hackerrank.com/challenges/compare-the-triplets
    Test: Alice=[5,6,7] Bob=[3,6,10] -> Output: 1 1

19. [LeetCode 1342] Number of Steps to Reduce a Number to Zero
    Given a number, if even divide by 2, if odd subtract 1. Count steps.
    Test: 14 -> 6 steps (14->7->6->3->2->1->0)

20. [LeetCode 13 - Simplified] Roman to Integer
    Read a Roman numeral string (I, V, X, L, C, D, M) and convert to integer.
    I=1, V=5, X=10, L=50, C=100, D=500, M=1000
    Rule: If smaller value before larger, subtract (IV=4, IX=9).
    Test: "XIV" -> 14 | "IX" -> 9 | "MCMXCIV" -> 1994

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