//↓template↓ #include "bits/stdc++.h" using namespace std; #define Would #define you #define all(n) n.begin(),n.end() #define rall(n) n.rbegin(),n.rend() typedef long long ll; const ll INF = 1e18; const ll MOD = 1e9 + 7; const double EPS = 1e-10; const double pi = acos(-1);//3.1415926535897932384626433832795028... const ll SIZE = 1 << 17; int dx[] = { 1,0,-1,0 }, dy[] = { 0,1,0,-1 }, alp[30]; ll fac[200005], finv[200005], inv[200005]; vectordij; struct edge { ll to, cost; }; vector >G; ll mod_pow(ll a, ll b) { ll res = 1, mul = a; for (int i = 0; i < 31; ++i) { if (b >> i & 1) { res *= mul; res %= MOD; } mul = (mul * mul) % MOD; } return res; } void addedge(int from, int to, int cost) { G[from].push_back({ to,cost }); G[to].push_back({ from,cost }); } template vector make_v(size_t a) { return vector(a); } template auto make_v(size_t a, Ts... ts) { return vector(ts...))>(a, make_v(ts...)); } template typename enable_if::value == 0>::type fill_v(T & t, const V & v) { t = v; } template typename enable_if::value != 0>::type fill_v(T & t, const V & v) { for (auto& e : t) fill_v(e, v); } template void outp(vectorv) { for (int i = 0; i < v.size(); ++i) { cout << v[i]; if (i != v.size() - 1) { cout << " "; } } } double add(double a, double b) { if (abs(a + b) < EPS * (abs(a) + abs(b))) { return 0; } return a + b; } //↑template↑ bool ok(string h) { if ((h.length() != 1 && h[0] == '0')) { return 0; } for (int i = 0; i < h.length(); ++i) { if (!isdigit(h[i])) { return 0; } } if (0 > stoi(h) || 12345 < stoi(h)) { return 0; } return 1; } int main() { string a, b, ans = "NG"; cin >> a >> b; if (ok(a) && ok(b)) { ans = "OK"; } cout << ans << endl; }