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0_0_12931620_10797\Main.java:1: 需要为 class、interface 或 enum
import java.util.*;importjava.math.*;public class Main {public static void main(String [] args)throws Exception{	Scanner cin=new Scanner(System.in);		BigInteger one=new BigInteger("1");		BigInteger zero=new BigInteger("0");		BigInteger two= new BigInteger("2");		BigInteger four= new BigInteger("4");		BigInteger six = new BigInteger("6");		BigInteger A;		BigInteger B;	int T;	T=cin.nextInt();	for(int tt=1;tt<=T;tt++){		String a,b;		a=cin.next();b=cin.next();		A=new BigInteger(a,2);		B=new BigInteger(b,2);		BigInteger ans=A.gcd(B);		System.out.print("Case #"+tt+": ");		System.out.println(ans.toString(2));	}}}