#include<iostream>
#include<string>
#include<cctype>
int main(){
    std::string input;
    std::getline(std::cin, input);
    bool hasDigit-false;
    std::string cleanedText=";
    for(char c:input){
        if(std::isdigit(c))){
        hasDigit - true;
        break;
    }
    if(c != ' '){
        cleaned Text+=c;
    }
    }
    if(hasDigit){
        std::count<<"Invalid input"<<std::endl;
    }else{std::cout<<cleanedText<<std::endl;
}
return 0;
}