Go: package main

import (
	"bufio"
	"os"
	"strings"
	"strconv"
	"reflect"
	"fmt"
)

var scanner = bufio.NewScanner(os.Stdin)

func scanBoard() [][]int {
	ret := make([][]int, 8)
	for k := range ret {
		ret[k] = make([]int, 8)
		for l := range ret[k] {
			ret[k][l] = 0
		}
	}
	for i := 0; i < 8; i++ {
		scanner.Scan()
		row := strings.Split(scanner.Text(), "")
		for j := 0; j < 8; j++ {
			ret[i][j], _ = strconv.Atoi(row[j])
		}
	}
	return ret
}

func main() {
	for {
		var board [][]int
		var ans string
		if board = scanBoard(); reflect.DeepEqual(board, [][]int{}) {
			break
		}
		fmt.Println(board)
		for i := 0; i < 7; i++ {
			for j := 0; j < 7; j++ {
				if board[i][j] == 1 && board[i+1][j] == 1 && board[i][j+1] == 1 && board[i+1][j+1] == 1 {
					ans = "A"
				}
			}
		}
		for i := 0; i < 5; i++ {
			for j := 0; j < 8; j++ {
				if board[i][j] == 1 && board[i+1][j] == 1 && board[i+2][j] == 1 && board[i+3][j] == 1 {
					ans = "B"
				}
			}
		}
		for i := 0; i < 8; i++ {
			for j := 0; j < 5; j++ {
				if board[i][j] == 1 && board[i][j+1] == 1 && board[i][j+2] == 1 && board[i][j+3] == 1 {
					ans = "C"
				}
			}
		}
		for i := 0; i < 6; i++ {
			for j := 0; j < 7; j++ {
				if board[i][j+1] == 1 && board[i+1][j] == 1 && board[i+1][j+1] == 1 && board[i+2][j] == 1 {
					ans = "D"
				}
			}
		}
		for i := 0; i < 7; i++ {
			for j := 0; j < 6; j++ {
				if board[i][j] == 1 && board[i][j+1] == 1 && board[i+1][j+1] == 1 && board[i+1][j+2] == 1 {
					ans = "E"
				}
			}
		}
		for i := 0; i < 7; i++ {
			for j := 0; j < 6; j++ {
				if board[i][j+1] == 1 && board[i][j+2] == 1 && board[i+1][j] == 1 && board[i+1][j+1] == 1 {
					ans = "G"
				}
			}
		}
		for i := 0; i < 6; i++ {
			for j := 0; j < 7; j++ {
				if board[i][j] == 1 && board[i+1][j] == 1 && board[i+1][j+1] == 1 && board[i+2][j+1] == 1 {
					ans = "F"
				}
			}
		}
		fmt.Println(ans)
	}
}

C++: #include <cstdio>
#include <iostream>

using namespace std;

char map[8][9];

char solve() {
	for (int i=0; i<8; ++i) {
		for (int j=0; j<8; ++j) {
			if (map[i][j] == '1') {
				if (i<7 && j<7 && map[i][j+1]=='1' && map[i+1][j]=='1' && map[i+1][j+1]=='1') return 'A';
				if (i<5 && map[i+1][j]=='1' && map[i+2][j]=='1' && map[i+3][j]=='1') return 'B';
				if (j<5 && map[i][j+1]=='1' && map[i][j+2]=='1' && map[i][j+3]=='1') return 'C';
				if (i<6 && map[i+1][j]=='1' && map[i+1][j-1]=='1' && map[i+2][j-1]=='1') return 'D';
				if (i<7 && j<6 && map[i][j+1]=='1' && map[i+1][j+1]=='1' && map[i+1][j+2]=='1') return 'E';
				if (i<6 && j<7 && map[i+1][j]=='1' && map[i+1][j+1]=='1' && map[i+2][j+1]=='1') return 'F';
				if (i<7 && j<7 && map[i][j+1]=='1' && map[i+1][j]=='1' && map[i+1][j+1]=='1') return 'G';
			}
		}
	}
}

int main() {
	while (scanf("%s", map[0]) != EOF) {
		for (int i=1; i<8; ++i) scanf ("%s", map[i]);
		char ans = solve();
		printf ("%c\n", ans);
	}
	return 0;
}

C++: #include<iostream>
#include<cstdio>
using namespace std;

int main(){
	char n[12][12];
	char figure[7][4][5] = {
		{"1100","1100","0000","0000"},
		{"1000","1000","1000","1000"},
		{"1111","0000","0000","0000"},
		{"0100","1100","1000","0000"},
		{"1100","0110","0000","0000"},
		{"1000","1100","0100","0000"},
		{"0110","1100","0000","0000"}
	};

	for(int i=0; i<12; i++)
		for(int j=0; j<12; j++)
			n[i][j]='0';
	
	while(~scanf("%8s\n%8s\n%8s\n%8s\n%8s\n%8s\n%8s\n%8s\n", n[0], n[1], n[2], n[3], n[4], n[5], n[6], n[7])){

		for(int i=0; i<7; i++){
			for(int j=0; j<8; j++){
				for(int k=0; k<8; k++){
					bool flag=true;
					
					for(int x=0; x<4; x++){
						for(int y=0; y<4; y++){
							if(figure[i][x][y] != n[j+x][k+y]) flag = false;
						}
					}
					
					if(flag){
						cout << (char)('A'+i) << endl;
					}

				}
			}
		}
	}
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define REP(i,n) for(int(i) = 0;(i)<(n);(i)++)
#define pb push_back
#define mp make_pair
#define All(X) X.begin(),X.end()

int main(){
	vector<int> vx, vy;
	while (1){
		vx.clear();
		vy.clear();
		REP(i, 8){
			string str;
			cin >> str;
			
			REP(j, 8){
				if (str[j] == '1'){
					vx.pb(i);
					vy.pb(j);
				}
			}
		}
		char ans = 'G';
		if (vx[0] == vx[1] && vy[0] == vy[2]) ans = 'A';
		if (vy[0] == vy[1] && vy[0] == vy[2] && vy[0] == vy[3]) ans = 'B';
		if (vx[0] == vx[1] && vx[0] == vx[2] && vx[0] == vx[3]) ans = 'C';
		if (vx[1] == vx[2] && vy[1] == vy[3] && vy[0] == vy[2]) ans = 'D';
		if (vx[0] == vx[1] && vx[2] == vx[3] && vy[1] == vy[2] && vy[0] + 2 == vy[3]) ans = 'E';
		if (vx[1] == vx[2] && vy[0] == vy[1] && vy[2] == vy[3]) ans = 'F';
		
		cout << ans << endl;
		if (cin.eof()){
			return 0;
		}
	}
}

C++: #include<cstdio>
#include<cstring>

int main(){
	char p[7][19] = {"1100000011", "10000000100000001", "1111", "1000000110000001", "11000000011", "100000001100000001", "110000011"};
	char f[65];
	char t;
	while(1 + scanf("%c", &t)){
		while(t == 10){
			scanf("%c", &t);
		}
		f[0] = t;
		for(int i = 1; i < 64; i++){
			scanf("%c", &t);
			while(t == 10){
				scanf("%c", &t);
			}
			f[i] = t;
		}
		f[64] = '\0';
		for(int i = 0; i < 7; i++){
			if(strstr(f, p[i])){
				printf("%c\n", i + 'A');
			}
		}
		scanf("%c", &t);
	}
	return 0;
}

C++: #include <iostream>
#include <stdio.h>
#include <string>
#include <math.h>
#include <algorithm>
#include <vector>
#include <map>
#include <cstdio>
#include <utility>

using namespace std;
typedef pair<double,double> P;




int main(){
	int field[8][8];
	string field1[8];
	
	while(cin >> field1[0]){
		for(int i = 1;i < 8;i++){
			cin >> field1[i];
		}
		for(int i = 0;i < 8;i++){
			for(int j = 0;j < 8;j++){
				if(field1[i][j] == '1') field[i][j] = 1;
				else field[i][j] = 0;
			}
		}
		/*for(int i = 0;i < 8;i++){
			for(int j = 0;j < 8;j++){
				cout << field[i][j];
			}
			cout << endl;
		}
		cout << endl;*/
		for(int i = 0;i < 8;i++){
			int flag = 0;
			for(int j = 0;j < 8;j++){
				if(field[i][j] == 1){
					//cout << i << j <<endl;
					if(field[i][j+1] == 1){
						if(field[i+1][j] == 1){
							if(field[i+1][j+1] == 1){
								cout << "A" << endl;
								flag = 1;break;
							}
							else if(field[i+1][j-1] == 1){
								cout << "G" << endl;
								flag = 1;break;
							}
						}
						else if(field[i][j+2] == 1 && field[i][j+3] == 1){
							cout << "C" << endl;
							flag = 1;break;
						}
						else if(field[i+1][j+1] == 1 && field[i+1][j+2] == 1){
							cout << "E" << endl;
							flag = 1;break;
						}
					}
					else if(field[i+1][j] == 1){
						if(field[i+1][j-1] == 1 && field[i+2][j-1] == 1){
							cout << "D" << endl;
							flag = 1;break;
						}
						else if(field[i+1][j+1] == 1 && field[i+2][j+1] == 1){
							cout << "F" << endl;
							flag = 1;break;
						}
					}
					else if(field[i+1][j] == 1 && field[i+2][j] == 1 && field[i+3][j] == 1){
						cout << "B" << endl;
						flag = 1;break;
					}
				}
			}
			if(flag == 1) break;
		}
	}

	return 0;
}