# 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 192192 x 1 = 192192 x 2 = 384192 x 3 = 576Concatenating the results: 192 384 576It 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.

#### ICSE

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``````import java.util.Scanner;

public class KboatFascinatingNumber
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.print("Enter the number to check: ");
int num = in.nextInt();

if (num < 100) {
System.out.println(num + " is not a Fascinating Number");
return;
}

int num2 = num * 2;
int num3 = num * 3;

boolean isFascinating = true;
String str = "" + num + num2 + num3;
for (char i = '1'; i <= '9'; i++) {
int idx1 = str.indexOf(i);
int idx2 = str.lastIndexOf(i);
if (idx1 == -1 || idx1 != idx2) {
isFascinating = false;
break;
}
}

if (isFascinating)
System.out.println(num + " is a Fascinating Number");
else
System.out.println(num + " is not a Fascinating Number");
}
}``````