Help me in solving SUMNEQ problem

help
,
1

My issue

I am unable to understand this question

My code

/* package codechef; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Codechef
{
	public static void main (String[] args) throws java.lang.Exception
	{
	    Scanner sc=new Scanner(System.in);
	    int n=sc.nextInt();
	    System.out.println(n-1);
	}
}

Problem Link: SUMNEQ Problem - CodeChef

2

a simple nested for loop will do your work.
for(i=0;i<n;i++){
for(j=0;j<n;j++){
if i+j==n
count++
it will check for every i if any j is present whose sum is n and thereby you can find your solution