OJ Board

my code is giving re. i couldnt find out the reason why?anyone plz help me to understand...

include<stdio.h>
#include<string.h>

int main()
{
long int step,modd,seed,seed1,cnt;

while(scanf("%ld%ld",&step,&modd)==2)
{
seed=0;
cnt=0;

seed1=(seed+step)%modd;
cnt++;

while(1)
{
if(seed1==0 ...