> #include <iostream.h>
> #include <math.h>
> void main()
> {
> 	int a,c,m,j,sum=0;
> 	cin>>a>>c>>m;
> 	int *r=new int[m];cin>>r[0];
> 	for (int i=1;i<m;i++){
> 		r[i]=(a*r[i-1]+c)%m;
> 		if(fabs(r[i]-r[i-1])>sum) sum= fabs(r[i]-r[i-1]) ;
> 		for (j=0;j<i;j++)
> 			if(r[j]==r[i])
> 				goto loop;
> 	}
> 	loop : cout<<sum<<endl;
> 	delete []r;
> }