#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<sstream>
bool isPalindrome(std::string s){
    std::string processed_s;
    for(char c : s){
        if(std::isalnum(static_cast<unsigned char>(c))){
            processed_s += std::tolower(static_cast<unsigned char>(c));
        }
    }
    std::string reversed_s =processed_s;
    std::reverse(reversed_s.begin(),reversed_s.end());
    return processed_s == reversed_s;
}
int main()
{
    std::string input;
    std::getline(std::cin,input);
    if(input.length()>100){
        std::cout<<"Invalid input"<<std::endl;
        return 0;
    }
    bool has_invalid_chars = false;
    bool has_dot = false;
    for(char c : input){
        if(c == '-'){
            has_invalid_chars = true;
            break;
        }
        if(c == '.'){
            has_dot = true;
        }
    }
    if(has_invlaid_chars || has_dot){
        std::cout<<"Invalid input"<<std::endl;
    }
    return 0;
}