Control Flow

public class ControlFlow {
    public static void main(String[] args) {
        int score = 85;

        if (score >= 90) System.out.println("A");
        else if (score >= 80) System.out.println("B");
        else if (score >= 70) System.out.println("C");
        else System.out.println("Below C");

        // Ternary
        String result = score >= 60 ? "Pass" : "Fail";

        // Enhanced switch expression (Java 14+)
        int day = 3;
        String dayName = switch (day) {
            case 1 -> "Monday";
            case 2 -> "Tuesday";
            case 3 -> "Wednesday";
            case 4 -> "Thursday";
            case 5 -> "Friday";
            case 6, 7 -> "Weekend";
            default -> "Invalid";
        };
        System.out.println(dayName);  // Wednesday

        // Classic switch (still valid)
        String quarter = switch (day) {
            case 1: case 2: case 3:
                yield "Q1";
            case 4: case 5: case 6:
                yield "Q2";
            default:
                yield "Later";
        };

        System.out.println(result);
    }
}

import java.util.List;

public class Loops {
    public static void main(String[] args) {
        // for loop
        for (int i = 0; i < 5; i++) {
            System.out.print(i + " ");
        }
        System.out.println();

        // Enhanced for (for-each)
        String[] fruits = {"apple", "banana", "cherry"};
        for (String fruit : fruits) {
            System.out.println(fruit);
        }

        // List with for-each
        List<Integer> numbers = List.of(1, 2, 3, 4, 5);
        for (int n : numbers) {
            System.out.print(n * n + " ");   // 1 4 9 16 25
        }
        System.out.println();

        // while
        int n = 10;
        while (n > 0) {
            System.out.print(n + " ");
            n -= 3;
        }
        System.out.println();

        // do-while — runs at least once
        int count = 0;
        do {
            count++;
        } while (count < 5);
        System.out.println("count: " + count);   // 5

        // Labels for nested loop control
        outer:
        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                if (i == 1 && j == 1) break outer;  // break outer loop
                System.out.print("(" + i + "," + j + ") ");
            }
        }
    }
}