Java: Generate and show the first 15 narcissistic decimal numbers

Last update on March 11 2025 11:10:13 (UTC/GMT +8 hours)

First 15 Narcissistic Numbers

Write a Java program to generate and show the first 15 narcissistic decimal numbers.

A Narcissistic decimal number is a non-negative integer, n that is equal to the sum of the m-th powers of each of the digits in the decimal representation of n, where m is the number of digits in the decimal representation of n.

• if n is 153
• then m , (the number of decimal digits) is 3
• we have 1³ + 5³ + 3³ = 1 + 125 + 27 = 153
• and so 153 is a narcissistic decimal number .

Pictorial Presentation:

Sample Solution:

Java Code:

// https://rosettacode.org/
public class Example6 {
	public static void main(String[] args){
		for(long n = 0, ctr = 0; ctr < 15; n++){
			if(is_narc_dec_num(n)){
				System.out.print(n + " ");
				ctr++;
			}
		}
		System.out.println();
	}
    public static boolean is_narc_dec_num(long n){
		if(n < 0) return false;
 
		String str1 = Long.toString(n);
		int x = str1.length();
		long sum_num = 0;
 
		for(char c : str1.toCharArray()){
			sum_num += Math.pow(Character.digit(c, 10), x);
		}
		return sum_num == n;
	}
 	
}

Sample Output:

0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to check if a number is narcissistic by recursively summing its digits raised to the power of the number of digits.
• Write a Java program to generate the next narcissistic number after a given input using an iterative approach.
• Write a Java program to find all narcissistic numbers within a specified range using Java streams.
• Write a Java program to compare the performance of recursive and iterative approaches in generating narcissistic numbers.

Java Code Editor:

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