OJ Board

it can run on my computer but ...online-judge give me Complie ERROR :evil:

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

int main()
{
int n=0,i=0,j[3000]={0};
bool isj=true;
while(1)
{
cin >> n;
if(cin.fail()) break;
for(i=0;i<n;i++)
{
cin >> j[i];
}
isj=true;
for(i=0;i ...