#include <algorithm>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>

using namespace std;

#define INF (1<<29)
#define EPS (1e-10)
#define make_pair mp
#define pb push_bacck

typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef pair<int,int> pii;

int dx[] = {0,1,0,-1}, dy[] = {1,0,-1,0};
int bx[7][4] = {
							{0,1,0,1},
							{0,0,0,0},
							{0,1,2,3},
							{1,0,1,0},
							{0,1,1,2},
							{0,0,1,1},
							{1,2,0,1}};
int by[7][4] = {
							{0,0,1,1},
							{0,1,2,3},
							{0,0,0,0},
							{0,1,1,2},
							{0,0,1,1},
							{0,1,1,2},
							{0,0,1,1}};

int main(){
	string board[8];
	string line;
	int l = 0;
	while (cin >> line) {
		board[l] = line;
		if (++l == 8) {
			for (int i = 0; i < 8; i++) {
				for (int j = 0; j < 8; j++) {
					for (int k = 0; k < sizeof(bx); k++) {
						bool ok = true;
						for (int l = 0; l < 4; l++) {
							int x = j+bx[k][l], y = i+by[k][l];
							if (x < 0 || 8 <= x || y < 0 || 8 <= y || board[y][x] != '1'){
								ok = false;
								break;
							}
						}
						if (ok) {
							cout << char('A'+k) << endl;
							goto end;
						}
					}
				}
			}
			end:;
			l = 0;
		}
	}
}