#include<iostream>
#include<string>
using namespace std;
int main()
{
    string text;
    getline(cin,text);
    if(text,length()==0)
    {
        cout<<"Invalid input";
        return 0;
    }
    for(char ch : text){
        if(isdigit(ch)){
            cout<<"Invaild input";
            return 0;
            
        }
    }
    string result =" ";
    for(char ch : text){
        if(ch!=' '){
            result+=ch;
        }
    }
    cout<<result;
    return 0;
}