Sum of Product

Sum or Product

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Write a program that asks the user for a number N and a choice C. And then give him the possibility to choose between computing the sum and computing the product of 1 ,..., N.

If user enters C is equal to -

 1 : Print sum of 1 to N numbers
 2 : Print product of 1 to N numbers
 Any other number : print -1

Input format :

Line 1 : Integer N
Line 2 : Choice C (1 or 2)

Output Format :

 Sum or product according to user's choice

Sample Input 1 :

10
1

Sample Output 1 :

55

Sample Input 2 :

10
2

Sample Output 2 :

3628800

Sample Input 3 :

10
4

Sample Output 3 :

-1

import java.util.Scanner;
public class Main
{
    public static void main(String[] args)
    {
        int i,sum=0,pro=1;
Scanner s = new Scanner(System.in);
     
      int n = s.nextInt();
     
     
      int n1 = s.nextInt();
     
    if(n1==1)
    {
   
    for(i=1;i<=n;i++)
{
sum=sum+i;
}
    System.out.println(sum);
    }
    else if(n1==2)
    {
    for(i=1;i<=n;i++)
{
pro=pro*i;


}
   
    System.out.println(pro);

    }
    else
 
    System.out.println(-1);


}
   
}