Page 201 - ComputerScience_Class_11

The syntax of the while loop is:

Initialisation;
while(test condition)
{
// body of the loop
increment or decrement;
}
For example:

Program 5 Write a Java program to check if a number is a sum product number. A sum product number is
a number for which the product of its digits multiplied by the sum of its digits is equal to the
original number.
1 import java.util.Scanner;

2 public class SumProductNumber {
3 public static void main(String[] args) {
4 Scanner sc = new Scanner(System.in);
5 System.out.print("Enter a number: ");
6 int n = sc.nextInt();
7 int r, sum = 0, product = 1, temp;

8 temp = n;
9 while (temp > 0) {
10 r = temp % 10;
11 sum = sum + r;

12 product = product * r;
13 temp = temp / 10;
14 }
15 if ((sum * product) == n) {
16 System.out.println(n + " is a sum product number");
17 } else {

18 System.out.println(n + " is not a sum product number");
19 }
20 sc.close();
21 }

22 }

The output of the preceding program is as follows:
BlueJ: Terminal Window - Java

Options

Enter a number: 135
135 is a sum product number

Since the condition is checked before the execution of the while loop, we can call it an Entry Controlled Loop.

Statements and Scope 199