Apr 17th, 2014 at 04:26 PM

Java program example to find factorial

This java program finds factorial of a number. Entered number is checked first if its negative then an error message is printed. Code

import java.util.Scanner;
 
class Factorial
{
   public static void main(String args[])
   {
      int n, c, fact = 1;
 
      System.out.println("Enter an integer to calculate it's factorial");
      Scanner in = new Scanner(System.in);
 
      n = in.nextInt();
 
      if ( n < 0 )
         System.out.println("Number should be non-negative.");
      else
      {
         for ( c = 1 ; c <= n ; c++ )
            fact = fact*c;
 
         System.out.println("Factorial of "+n+" is = "+fact);
      }
   }
}

Compile and Run: You can also find factorial using recursion, in the code fact is an integer variable so only factorial of small numbers will be correctly displayed or which fits in 4 bytes. For large numbers you can use long data type.