#include<bits/stdc++.h>
using namespace std;
int main(){
	string s1,s2;
	cin>>s1>>s2;
	if(s1.size()>s2.size()){
		for(int i=0;i<s2.size();i++){
			if(s1[i]!=s2[i]){
				cout<<s1[i]-s2[i];
				return 0;
			}
		}
	}else{
		for(int i=0;i<s1.size();i++){
			if(s1[i]!=s2[i]){
				cout<<s1[i]-s2[i];
				return 0;
			}
		}
	}
	
	
	
	return 0;
}

/**************************************************************
	Problem: 1848
	User: tangkaixuan
	Language: C++
	Result: Wrong Answer
****************************************************************/