65 lines
2.2 KiB
Java
65 lines
2.2 KiB
Java
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/**
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* A number is said to be Dudeney if the sum of the digits, is the cube root of the entered number.
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* Example- Let the number be 512, its sum of digits is 5+1+2=8. The cube root of 512 is also 8.
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* Since, the sum of the digits is equal to the cube root of the entered number;
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* it is a Dudeney Number.
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*/
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package Maths;
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import java.io.*;
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public class DudeneyNumber
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{
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//returns True if the number is a Dudeney number and False if it is not a Dudeney number.
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public static boolean isDudeney(int n)
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{
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// Calculating Cube Root
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int cube_root = (int)(Math.round((Math.pow(n, 1.0 / 3.0))));
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// If the number is not a perfect cube the method returns false.
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if (cube_root * cube_root * cube_root != n)
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return false;
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int sum_of_digits = 0;// Stores the sums of the digit of the entered number
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int temp = n;//A temporary variable to store the entered number
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// Loop to calculate sum of the digits.
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while (temp > 0)
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{
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// Extracting Last digit of the number
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int rem = temp % 10;
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// Calculating sum of digits.
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sum_of_digits += rem;
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// Removing the last digit
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temp /= 10;
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}
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//If the cube root of the number is not equal to the sum of its digits we return false.
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if (cube_root != sum_of_digits)
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return false;
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return true;
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}
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/** Method to check if number is Dudeney Number or Not
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* 1) Input - Enter a Number: 512
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* Output - It is a Dudeney Number.
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* 2) Input - Enter a Number: 125
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* Output - It is not a Dudeney Number.
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*/
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public static void main(String args[]) throws IOException
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{
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BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
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System.out.println("Enter a Number: ");
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int n=Integer.parseInt(br.readLine());
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if(isDudeney(n))
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{
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System.out.println("It is a Dudeney Number.");
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}
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else
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{
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System.out.println("It is not a Dudeney Number.");
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}
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}
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}
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