##include<iostream>
#include<cctype>
using namespace std;
int main()
{
    string s;
    cin>>s;
    if(s.empty()){
        cout<<"false";
        return 0;
    }
    for(char c:s){
        if(!isdigit(c)){
            cout<<"False";
            retirn 0;
        }
    }
}