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<iostream>
#include<vector>
#include<stdio.h>
using namespace std;

int main(){
    char boa[8][8];
    while(1){
        
        for(int i=0;i<8;i++){
            for(int j=0;j<8;j++){
                if(!(cin>>boa[i][j]))
                    return 0;
            }
        }
        int bo[8][8];
        for(int i=0;i<8;i++){
            for(int j=0;j<8;j++){
                bo[i][j]=boa[i][j]-'0';
            }
        }
            
        for(int i=0;i<8;i++){
            for(int j=0;j<8;j++){
                if(bo[i][j]==1){
                    if(i<8&&j<8){
                        if(bo[i+1][j]==1&&bo[i][j+1]==1&&bo[i+1][j+1]){
                            cout<<"A"<<endl;
                            goto next;
                        }
                    }
                    if(j<4){
                        if(bo[i][j+1]&&bo[i][j+2]&&bo[j+3]){
                            cout<<"C"<<endl;goto next;
                        }
                            
                    }
                    if(i<4){
                        if(bo[i+1][j]&&bo[i+2][j]&&bo[i+3][j]){
                            cout<<"B"<<endl;goto next;
                        }
                        
                    }
                    if(i<7&&i>0&&j<7){
                        if(bo[i+1][j]&&bo[i][j+1]&&bo[i-1][j+1]){
                            cout<<"D"<<endl;goto next;
                        }
                    }
                    if(i<7&&j<6){
                        if(bo[i][j+1]&&bo[i+1][j+1]&&bo[i+1][j+2]){
                            cout<<"E"<<endl;goto next;
                        }
                    }
                    if(i<6&&j<7){
                        if(bo[i+1][j]&&bo[i+1][j+1]&&bo[i+2][j+1]){
                            cout<<"F"<<endl;goto next;
                        }
                    }
                    if(i<6&&j>0){
                        if(bo[i+1][j]&&bo[i+1][j-1]&&bo[i][j+1]){
                            cout<<"G"<<endl;goto next;
                        }
                    }
                    
                }
            }
        }
        
    next:;
    }
    
    return 0;
}

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

int main()
{
    char field[11][11];
    string r;
    int i,j;
    do {
	for (i=0; i<8; i++)
	{
	    scanf("%s",field[i]);
	}
	for (i=0; i<8; i++)
	{
	    for (j=0; j<8; j++)
	    {
		if (field[i][j] == '1')goto b;
	    }
	}
    b:
	if (field[i][j+1] == '1')
	{
	    if (field[i][j+2] == '1')
		r="C";
	    else if (field[i+1][j] == '1') {
		if (field[i+1][j+1] == '1')
		    r="A";
		else
		    r="G";
	    }
	    else
		r="E";
	} else {
	    if (field[i+2][j] == '1')
		r="B";
	    else if (field[i+1][j+1] == '1')
		r="F";
	    else
		r="D";
	}
	cout << r << endl;
	getchar();
    } while (getchar() != EOF);
    return 0;
}

C++: #include <fstream>
#include <iostream>
#include <cmath>
#include <vector>
#include <queue>
#include <utility>
#include <algorithm>
using namespace std;

int main() {
  // ifstream cin("../test.txt");
  char a[8][8];
  char c;

  vector<string> shape(7);
  shape[0] = "1100110000000000";
  shape[1] = "1000100010001000";
  shape[2] = "1111000000000000";
  shape[3] = "0100110010000000";
  shape[4] = "1100011000000000";
  shape[5] = "1000110001000000";
  shape[6] = "0110110000000000";

  while (cin >> c) {
    a[0][0] = c;
    for (int i = 1; i < 8; i++) {
      cin >> c;
      a[0][i] = c;
    }
    for (int i = 1; i < 8; i++) {
      for (int j = 0; j < 8; j++) {
        cin >> c;
        a[i][j] = c;
      }
    }

    // for (int i = 0; i < 8; i++) {
    //   for (int j = 0; j < 8; j++) {
    //     cout << a[i][j];
    //   }
    //   cout << endl;
    // }


    int h,w;
    for (int i = 0; i < 64; i++) {
      if (a[i/8][i%8] == '1') {
        h = i / 8;
        w = i % 8;
        break;
      }
    }

    // cout << h << " " << w << endl;

    for (int s = 0; s < 7; s++) {
      bool flag = true;
      for (int i = 0; i < 4; i++) {
        for (int j = 0; j < 4; j++) {
          if (shape[s][4 * i + j] != a[h + i][w + j])
            flag = false;
        }
      }

      if (flag) {
        cout << (char)('A' + s) << endl;
        break;
      }
    }

  }
}

C++: /* ??????????????´ */

#include <cstdio>
#include <cassert>
using namespace std;

int field[8][8];

int adx[] = {0, 0, 1, 1};
int ady[] = {0, 1, 0, 1};

int bdx[] = {0, 0, 0, 0};
int bdy[] = {0, 1, 2, 3};

int cdx[] = {0, 1, 2, 3};
int cdy[] = {0, 0, 0, 0};

int ddx[] = {0, 1, 1, 0};
int ddy[] = {0, 0, -1, 1};

int edx[] = {0, 1, 1, 2};
int edy[] = {0, 0, 1, 1};

int fdx[] = {0, 0, 1, 1};
int fdy[] = {0, 1, 1, 2};

int gdx[] = {0, 1, 0, -1};
int gdy[] = {0, 0, 1, 1};


bool WithinRange(int y, int x) {
  if (x < 0) return false;
  if (x >= 8) return false;
  if (y < 0) return false;
  if (y >= 8) return false;

  return true;
}

bool Match(int *dx, int *dy) {
  for (int i=-2; i<10; i++) {
    for (int j=-2; j<10; j++) {
      int sum = 0;

      for (int k=0; k<4; k++) {
        int newy = i+dy[k];
        int newx = j+dx[k];
        if (WithinRange(newy, newx)) sum += field[newy][newx];
      }

      if (sum == 4) return true;
    }
  }

  return false;
}

int main() {
  while (1) {
    for (int i=0; i<8; i++) {
      for (int j=0; j<8; j++) {
        char c;
        if (scanf(" %c", &c) != 1) return 0;
        field[i][j] = (c == '1');
      }
    }

    if (Match(adx, ady)) puts("A");
    else if (Match(bdx, bdy)) puts("B");
    else if (Match(cdx, cdy)) puts("C");
    else if (Match(ddx, ddy)) puts("D");
    else if (Match(edx, edy)) puts("E");
    else if (Match(fdx, fdy)) puts("F");
    else if (Match(gdx, gdy)) puts("G");
    else assert(0);
  }
}