java ,why this solution for YVNUM showing error NZEC

i/ANY body who can find out the mistake ,reply please
while submitting showing “ERROR NZEC”
/

mport java.util.Scanner;
import java.math.BigInteger;
import java.math.*;
class Main
{
public static void main(String []args) throws Exception
{

int t;
Scanner s=new Scanner(System.in);
t=s.nextInt();
for(int i=0;i<t;i++)
{
	int n,l=0,m;
	n=s.nextInt();
	m=n;
	while(n>0)
	{l++;n=n/10;}
	n=m;
	int [] a=new int[l];
	for(int k=0;k<l;k++)
	{
		a[k]=n%10;
		n=n/10;
	}
	
	int []b=new int [l];
	BigInteger r=new BigInteger("0");
	if(Main.check(a,l))
	{
		for(int f=0;f<l;f++)
		b[f]=a[l-f-1];
		for(int j=0;j<l;j++)
		{
		    for(int u=0;u<l;u++)
			r=r.multiply(BigInteger.valueOf(10)).add(BigInteger.valueOf(b[u]));
		    Main.rotate(b,l);
		}
		r=r.mod(BigInteger.valueOf((long)(Math.pow(10,9)+7)));
		System.out.println(r+"\n");
	}
}

}

public static boolean check(int []a,int l)
{
int sum=0;
for(int i=0;i<l;i++)
{
sum=sum+a[i];
}
if(sum>(int)Math.pow(10,6))
return false;
for(int i=0;i<l;i++)
{
if(a[i]==0)
return false;

}

return true;
}

public static void rotate(int []a,int l)
{ int t;
for(int i=0;i<l-1;i++)
{
t=a[i];
a[i]=a[i+1];
a[i+1]=t;
}
}

}

//