#include
int main()
{
    int X,Y,K,i;
    scanf("%d %d %d",&X,&Y,&K);
    if((X-Y)%K!=0 || (Y-X)%K!=0)
    {
        printf("ERROR");
    }
    else
    {
        if(X>Y)
        {
            for(i=X;i>=Y;i-=K)
            {
                if(i==Y)
                {
                    printf("Reached!");
                    break;
                }
                else
                    printf("%d, ",i*i);
            }
        }
        else if(X