#include<iostream> using namespace std; bool Alp(string s){ bool ret=false; for(int i=0; i<s.size(); i++){ ret|=(('a'<=s[i]&&s[i]<='z')||('A'<=s[i]&&s[i]<='Z')); } return ret; } bool Zero(string s){ return (s[0]=='0')&(s.size()>1); } int main(){ string A, B; cin>> A>> B; if(Alp(A)||Alp(B)){ cout<< "NG"<< endl; return 0; } if(Zero(A)||Zero(B)){ cout<< "NG"<< endl; return 0; } if(stoi(A)<=12345&&stoi(B)<=12345){ cout<< "OK"<< endl; }else{ cout<< "NG"<< endl; } return 0; }