Java Programming Lesson 4 | Conditional Statements Tutorial for Beginners

LESSON-4: CONDITIONAL STATEMENTS

🚀 Let's move to Lesson-4: Conditional Statements
(Real-life logic in Java ✅)

📘 Lesson 4 — Conditional Statements (if, else, switch)

Conditional statements are used when your program must decide something based on conditions.

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✅ 1️⃣ if Statement

Executes code only if condition is true.

if (condition) {
    // code
}

Example

int age = 18;

if(age >= 18){
    System.out.println("You are an adult.");
}

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✅ 2️⃣ if...else Statement

If condition true → first block
Else → second block

int marks = 40;

if(marks >= 50){
    System.out.println("Pass");
} else {
    System.out.println("Fail");
}

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✅ 3️⃣ else if Statement

Used for multiple conditions

int marks = 85;

if(marks >= 90){
    System.out.println("A+");
} else if(marks >= 80){
    System.out.println("A");
} else {
    System.out.println("Try Again");
}

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✅ 4️⃣ switch Statement

Better for fixed values (menu, grades, days)

int day = 3;

switch(day){
    case 1:
        System.out.println("Monday");
        break;
    case 2:
        System.out.println("Tuesday");
        break;
    case 3:
        System.out.println("Wednesday");
        break;
    default:
        System.out.println("Invalid Day");
}

📌 break = stops switching
📌 default = fallback option

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✅ Full Practical Example

import java.util.Scanner;

public class ConditionsExample {
    public static void main(String[] args) {
        
        Scanner input = new Scanner(System.in);
        System.out.print("Enter your age: ");
        int age = input.nextInt();

        if(age >= 18){
            System.out.println("Eligible for Voting");
        } else {
            System.out.println("Not Eligible");
        }

        System.out.println("Enter day number (1-7): ");
        int day = input.nextInt();

        switch(day){
            case 1: System.out.println("Monday"); break;
            case 2: System.out.println("Tuesday"); break;
            case 3: System.out.println("Wednesday"); break;
            case 4: System.out.println("Thursday"); break;
            case 5: System.out.println("Friday"); break;
            case 6: System.out.println("Saturday"); break;
            case 7: System.out.println("Sunday"); break;
            default: System.out.println("Invalid Day");
        }
    }
}

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📝 Exercise for You ✅

Write a program:

📌 Input
A number from user

📌 Output
Check and print whether:

✅ Positive or Negative
✅ Even or Odd
✅ Number category using switch (1 → "One", 2 → "Two", otherwise → "Other Number")

You must use:

✔ if
✔ else-if
✔ switch

Reply with:
✅ Your Code
✅ Output Screenshot or text

I will grade it ✅🔥

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🎯 Quick Quiz

1️⃣ Which keyword stops switch case?
A) stop
B) exit
C) break

2️⃣ Choose valid condition:
A) if x = 10
B) if(x == 10)
C) if(x => 10)

Reply: 1 → ?, 2 → ?

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✅ Lesson-4 Completed!

When you're ready →
➡ Lesson-5: Loops (for, while, do-while) 🚀

Send your exercise + quiz answers below 👇😊

▶ NEXT PART - Lesson-5: Loops