Calculates the Greatest Common Divisor of two numbers passed into the program through command line arguments. : Math « Development Class « Java






  1. Java
  2. Development Class
  3. Math

Calculates the Greatest Common Divisor of two numbers passed into the program through command line arguments.

        
//package numeric;

/**
* This class calculates the Greatest Common
* Divisor of two numbers passed into the program
* through command line arguments.
*
* @author Alex Laird
* @version 1.0
* File: GCD.java
* Created: Sep 2008
*/
public class GCD
{
     /**
     * Returns the Greatest Common Divisor of two
     * numbers that are passed into the method.
     *
     * @param a the first integer for comparison.
     * @param b the second integer for comparison.
     * @throws NegativeNumberException if the input given is negative.
     * @returns the Greatest Common Divisor.
     */
     public static int gcd(int a, int b) throws Exception
     {
         // throw an exception if the input is negative
         if(a < 0 || b < 0)
         {
             throw new Exception("The user has entered a "
                                               + "negative number.");
         }

          if(b == 0)
               return a;
          else
               return gcd(b, a % b);
     }

     /**
     * The main method from which the program executes;
     * it handles all I/O and method execution.
     *
     * @param args Arguments received from the command line (two numbers).
     * @param gcd The calcuated Greatest Common Divisor of args[0] and args [1].
     */
     public static void main(String[] args)
     {
          // ensure the user only enters two arguments
          if(args.length == 2)
          {
               // ensure the users arguments are numbers
               try
               {
                    // calculate gcd
                    int gcd = gcd(Integer.parseInt(args[0]),
                              Integer.parseInt(args[1]));

                    System.out.println("The Greatest Common Divisor of "
                                       + args[0] + " and " + args[1] + " is "
                                       + gcd + ".");
               }
               catch(NumberFormatException c)
               {
                    System.out.println("Your arguments must be in "
                                       + "the form of integers when "
                                       + "running the program (ex. "
                                       + "enter 'java numeric.GCD "
                                       + "50 30').");
               }
               catch(Exception c)
               {
                    // used only in GUI
               }

          }
          else
          {
               System.out.println("Enter two numbers as arguments "
                                  + "when running the program (ex. "
                                  + "enter 'java numeric.GCD 50 30').");
          }
     }
}








Related examples in the same category

1.Absolute value
2.Find absolute value of float, int, double and long using Math.abs
3.Find ceiling value of a number using Math.ceil
4.Find exponential value of a number using Math.exp
5.Find floor value of a number using Math.floor
6.Find minimum of two numbers using Math.min
7.Find power using Math.pow
8.Find square root of a number using Math.sqrt
9.Find natural logarithm value of a number using Math.log
10.Find maximum of two numbers using Math.max
11.Get the power valueGet the power value
12.Using the Math Trig MethodsUsing the Math Trig Methods
13.Using BigDecimal for PrecisionUsing BigDecimal for Precision
14.Demonstrate our own version round()Demonstrate our own version round()
15.Demonstrate a few of the Math functions for TrigonometryDemonstrate a few of the Math functions for Trigonometry
16.Exponential DemoExponential Demo
17.Min Demo
18.Basic Math DemoBasic Math Demo
19.Using strict math in applicationsUsing strict math in applications
20.Conversion between polar and rectangular coordinates
21.Using the pow() function
22.Using strict math at the method level
23.Calculating hyperbolic functions
24.Calculating trigonometric functions
25.Weighted floating-point comparisons
26.Solving right triangles
27.Applying the quadratic formula
28.Calculate the floor of the log, base 2
29.Greatest Common Divisor (GCD) of positive integer numbers
30.Least Common Multiple (LCM) of two strictly positive integer numbers
31.Moving Average
32.Make Exponention
33.Caclulate the factorial of N
34.Trigonometric DemoTrigonometric Demo
35.Complex Number Demo
36.sqrt(a^2 + b^2) without under/overflow
37.Returns an integer hash code representing the given double array value.
38.Returns an integer hash code representing the given double value.
39.Returns n!. Shorthand for n Factorial, the product of the numbers 1,...,n as a double.
40.Returns n!. Shorthand for n Factorial, the product of the numbers 1,...,n.
41.Returns the hyperbolic sine of x.
42.Contains static definition for matrix math methods.
43.For a double precision value x, this method returns +1.0 if x >= 0 and -1.0 if x < 0. Returns NaN if x is NaN.
44.For a float value x, this method returns +1.0F if x >= 0 and -1.0F if x < 0. Returns NaN if x is NaN.
45.Normalize an angle in a 2&pi wide interval around a center value.
46.Normalizes an angle to a relative angle.
47.Normalizes an angle to an absolute angle
48.Normalizes an angle to be near an absolute angle
49.Returns the natural logarithm of n!.
50.Returns the least common multiple between two integer values.
51.Gets the greatest common divisor of the absolute value of two numbers
52.Matrix manipulation
53.Returns exact (http://mathworld.wolfram.com/BinomialCoefficient.html) Binomial Coefficient
54.Returns a double representation of the (http://mathworld.wolfram.com/BinomialCoefficient.html) Binomial Coefficient
55.Returns the natural log of the (http://mathworld.wolfram.com/BinomialCoefficient.html) Binomial Coefficient
56.Returns the hyperbolic cosine of x.
57.Math Utils
58.Implements the methods which are in the standard J2SE's Math class, but are not in in J2ME's.
59.Utility methods for mathematical problems.
60.A math utility class with static methods.
61.Computes the binomial coefficient "n over k"
62.Log Gamma
63.Log Beta
64.Beta
65.Gamma
66.Factorial
67.Computes p(x;n,p) where x~B(n,p)
68.Returns the sum of two doubles expressed in log space
69.sigmod
70.sigmod rev
71.Numbers that are closer than this are considered equal
72.Returns the KL divergence, K(p1 || p2).
73.Returns the sum of two doubles expressed in log space
74.Returns the difference of two doubles expressed in log space
75.Is Prime
76.Statistical functions on arrays of numbers, namely, the mean, variance, standard deviation, covariance, min and max
77.This class calculates the Factorial of a numbers passed into the program through command line arguments.This class calculates the Factorial of a numbers passed into the program through command line arguments.
78.Variance: the square of the standard deviation.
79.Population Standard Deviation
80.Returns from a static prime table the least prime that is greater than or equal to a specified value.