#include<iostream>
using namespace std;
bool valid(string s){
    for(char c:s)
    if(c<'a'||c>'z')
    return false;
}
int main(){
    string s1,s2;
    cin>>s1>>s2;
    if(!valid(s1)||!valid(s2)){
        cout<<"Invalid input";
    }
    else if(s1.length()==s2.length()&&s2==s2.substr(2)+s1.subtr(0,2)){
        cout<<"true";
    }
    else{
        cout<<"false";
    }
    return 0;
}