using namespace std;


int main() {

//code
	
int t;
	
cin>>t;
  
	while(t--)

	{
	 
	   int count=0;

	    string s,p;

	    cin>>s;
	    cin>>p;
	    
	    for(int i=0;i<s.length();i++)
	 
 	   {
	       
		 if(s[i]!=p[i])
	     
		   count++;
	  
	  }
	  
	  if(count==2)
	   
	 cout<<1<<endl;
	   
	 else
	 
	   cout<<0<<endl;
	

	}
	
return 0;
}