StrongNumber.java

import java.util.ArrayList;
import java.util.Scanner;
import java.util.List;

public class StrongNumber {
    public static int factorial(int n) {
        if (n < 1) return 1;
        return n * factorial(n - 1);
    }
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        List<Integer> strongNumbers = new ArrayList<>();

        int size = sc.nextInt();
        int i = 0;
        // loop until positive numbers of queue size are received
        while (i < size) {
            System.out.println("Enter number " + i + ": ");
            int num = sc.nextInt();

            if (num >= 0) {
                i++;
                int n = num;
                int sum = 0;
                // break the number to extract each digit
                while (n > 0) {
                    int digit = n % 10;
                    // calculate factorial
                    int fact = factorial(digit);
                    // add to sum
                    sum += fact;
                    // update the number
                    n /= 10;
                }

                if (sum == num) {
                    strongNumbers.add(num);
                }
            } else {
                System.out.println("Enter positive number only.");
            }
        }

        System.out.print("Strong numbers are: ");
        for (int strongNumber: strongNumbers) {
            System.out.print(strongNumber + " ");
        }
    }
}

In the TCS NQT exam environment, the Java compiler was likely configured with flags that enforce stricter type checking and treat warnings as errors. Specifically, it might have used flags like:

-Xlint:unchecked - This flag enables warnings for unchecked operations, like using raw types.
-Werror - This flag treats all warnings as errors, preventing compilation if any warning occurs.