#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
#define pii pair<int, int>
#define all(x) (x).begin(), (x).end()
bool be;
constexpr int N = 12;
int a[N][N];
bool vis[N];
bool en;
int main()
{
#ifdef IAKIOI
	freopen("in.in", "r", stdin);
//	freopen("out.out", "w", stdout);
	cerr << (&be - &en) / 1024.0 / 1024 << '\n' << "-------------------\n";
#endif
//	ios::sync_with_stdio(false);
//	cin.tie(nullptr);
	scanf("+---+---+---+\n");
	for (int i = 1; i <= 9; ++i) {
		scanf("|");
		for (int j = 1; j <= 9; ++j) {
			char c;
			cin >> c;
			if (isdigit(c)) a[i][j] = c - '0';
			if (j % 3 == 0) scanf("|");
		}
		scanf("\n");
		if (i % 3 == 0) scanf("+---+---+---+\n");
	}
	for (int i = 1; i <= 9; ++i) {
		memset(vis, 0, sizeof vis);
		for (int j = 1; j <= 9; ++j) {
			if (!a[i][j]) continue;
			if (vis[a[i][j]]) {
				cout << "GRESKA\n";
				return 0;
			}
			vis[a[i][j]] = 1;
		}
	}
	for (int i = 1; i <= 9; ++i) {
		memset(vis, 0, sizeof vis);
		for (int j = 1; j <= 9; ++j) {
			if (!a[j][i]) continue;
			if (vis[a[j][i]]) {
				cout << "GRESKA\n";
				return 0;
			}
			vis[a[j][i]] = 1;
		}
	}
	for (int i : {1, 4, 7}) {
		for (int j : {1, 4, 7}) {
			memset(vis, 0, sizeof vis);
			for (int k : {0, 1, 2}) {
				for (int l : {0, 1, 2}) {
					if (!a[i + k][j + l]) continue;
					if (vis[a[i + k][j + l]]) {
						cout << "GRESKA\n";
						return 0;
					}
					vis[a[i + k][j + l]] = 1;
				}
			}
		}
	}
	cout << "OK\n";
	return 0;
}