Programming Examples
Java program for fascinating numbers
Write a Program in Java to input a number and check whether it is a Fascinating Number or not.
Fascinating Numbers: Some numbers of 3 digits or more exhibit a very interesting property. The property is such that, when the number is multiplied by 2 and 3, and both these products are concatenated with the original number, all digits from 1 to 9 are present exactly once, regardless of the number of zeroes.
Let’s understand the concept of Fascinating Number through the following example:
Consider the number 192, 192 x 1 = 192 192 x 2 = 384 192 x 3 = 576
Concatenating the results : 192384576
It could be observed that ‘192384576’ consists of all digits from 1 to 9 exactly once. Hence, it could be concluded that 192 is a Fascinating Number.
Some examples of fascinating Numbers are : 192, 219, 273, 327, 1902, 1920, 2019 etc.
Sample Data:
Enter a number : 273
273 is a Fascinating Number.
Enter a number : 853
853 is not a Fascinating Number.
Enter a number : 95
Number should be of atleast 3 digits.
Solution
import java.util.*;
class Fascinating
{
public static void main(String args[])
{
Scanner sc=new Scanner(System.in);
System.out.print("Enter any Number : ");
int n = sc.nextInt();
int n2 = n * 2;
int n3 = n * 3;
String con = n + "" + n2 + n3;
boolean found = true;
for(char i = '1'; i <= '9'; i++)
{
int count = 0;
for(int j = 0; j < con.length(); j++)
{
char ch = con.charAt(j);
if(ch == i)
count++;
}
if(count > 1 || count == 0)
{
found = false;
break;
}
}
if(found)
System.out.println(n + " is a fascinating number.");
else
System.out.println(n + " is not a fascinating number.");
}
}
Output
Enter any Number : 192
192 is a fascinating number.
Enter any Number : 273
273 is a fascinating number.
Enter any Number : 100
100 is not a fascinating number.