Uva--10161--ant on a chessboard

It's a simple math problem, but it takes some time to find out the rules.

My idea is: to find the coordinates of 3 points for each basic graph and the relationship between the time, and then the other points are classified by these 3 points to discuss the results

The code is as follows:

#include <iostream>
#include <cmath>
using namespace std;

int main ()
{
    int n,x,y,a,b,i,sn,n;
    while (Cin>>n&&n)
    {
         double m=n;
         N= (sqrt ((double) m)-1)/2; 
         sn=4*n*n+4*n+1;
         a=4*n*n+6*n+3;
         b=4*n*n+10*n+7;
         if (sn==n)
         {
            y=2*n+1;
            x=1;
         }
         else if (n<=a)
         {
            x=2*n+2-(a-n);
            y=2*n+2;
         } 
         else if ((4*n*n+8*n+4) >=n)
         {
              x=2*n+2;
              y=1+ (4*n*n+8*n+4-n);
         }
         else if (n<=b)
         {
              x=2*n+2+1;
              y=2*n+3-(b-n);
         }
         else
         {
            x=2*n+3+ (b-n);
            y=2*n+3;
         }
         cout<<x<< "" <<y<<endl;
    }
  return 0;
}