Sum or Product

********* Problem Statment **********

Write a program that asks the user for a number N and a choice C. And then give them the possibility to choose between computing the 
sum and computing the product of all integers in the range 1 to N (both inclusive).




****** Solution (Java Code) *******

import java.util.Scanner;
public class Main {
	
	public static void main(String[] args) {
		
      int n,c,i,sum=0,mul=1;
	        Scanner sc=new Scanner(System.in);
	        n=sc.nextInt();
	        c=sc.nextInt();
	      	if(c==1)
	        {
	            while(n<13 && n>0)
	            {
	                sum=sum+n;
	                
	                n--;
	            }
	            System.out.println(sum);
	        }
	      	else if(c==2)
	      	{
	      		while(n>0)
	      		{
	      			mul=mul*n;
	      			n--;
	      		}
	      		 System.out.println(mul);
	      	}
	      	else
	      	{
	      		System.out.println(-1);
	      	}

	}
}