Programming Example
Using a switch statement, write a menu driven program to:
Study this program carefully to understand the logic, output, and explanation in a structured way.
Using a switch statement, write a menu driven program to:
(a) Generate and display the first 10 terms of the Fibonacci series
0, 1, 1, 2, 3, 5
The first two Fibonacci numbers are 0 and 1, and each subsequent number is the sum of the previous two.
(b) Find the sum of the digits of an integer that is input.
Sample Input: 15390
Sample Output: Sum of the digits = 18
For an incorrect choice, an appropriate error message should be displayed.
import java.util.Scanner;
public class KboatFibonacciNDigitSum
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.println("1. Fibonacci Series");
System.out.println("2. Sum of digits");
System.out.print("Enter your choice: ");
int ch = in.nextInt();
switch (ch) {
case 1:
int a = 0, b = 1;
System.out.print(a + " " + b);
for (int i = 3; i <= 10; i++) {
int term = a + b;
System.out.print(" " + term);
a = b;
b = term;
}
break;
case 2:
System.out.print("Enter number: ");
int num = in.nextInt();
int sum = 0;
while (num != 0) {
sum += num % 10;
num /= 10;
}
System.out.println("Sum of Digits " + " = " + sum);
break;
default:
System.out.println("Incorrect choice");
break;
}
}
}1. Fibonacci Series
2. Sum of digits
Enter your choice: 1
0 1 1 2 3 5 8 13 21 34Press any key to continue . . .
1. Fibonacci Series
2. Sum of digits
Enter your choice: 2
Enter number: 15
Sum of Digits = 6
Press any key to continue . . .
First read the algorithm, then study the program code line by line. After that, compare the code with the output and finally go through the explanation. This approach helps learners understand both the logic and the implementation properly.
After understanding this example, try to rewrite the same program without looking at the code. Then change some values or logic and run it again. This helps improve confidence and keeps learners engaged on the page for longer.