#include<iostream> #include<vector> #include<string> #include<cstring> #include<algorithm> #include<map> #include<set> #include<cmath> #include<cassert> #include<queue> using namespace std; typedef long long ll; typedef unsigned long long ull; typedef pair<int, int> pii; typedef vector<int> vi; bool isNum(string S) { if (S == "0") return true; if (S[0] == '0') return false; for (char c : S) { if ('0' <= c && c <= '9') { } else return false; } return true; } void no() { cout << "NG" << endl; exit(0); } int main() { string A, B; cin >> A >> B; if (!isNum(A) || !isNum(B)) no(); int a = stoi(A), b = stoi(B); if (a < 0 || a > 12345) no(); if (b < 0 || b > 12345) no(); cout << "OK" << endl; return 0; }