Go: package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"strconv"
)

func configure(scanner *bufio.Scanner) {
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
}
func getNextString(scanner *bufio.Scanner) string {
	scanned := scanner.Scan()
	if !scanned {
		panic("scan failed")
	}
	return scanner.Text()
}
func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}
func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}
func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}
func main() {
	fp := os.Stdin
	wfp := os.Stdout
	extra := 0
	if os.Getenv("I") == "IronMan" {
		fp, _ = os.Open(os.Getenv("END_GAME"))
		extra = 100
	}
	scanner := bufio.NewScanner(fp)
	configure(scanner)
	writer := bufio.NewWriter(wfp)
	defer func() {
		r := recover()
		if r != nil {
			fmt.Fprintln(writer, r)
		}
		writer.Flush()
	}()
	solve(scanner, writer)
	for i := 0; i < extra; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
}
func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	dy := [4]int{-1, 0, 0, 1}
	dx := [4]int{0, -1, 1, 0}
	for {
		h := getNextInt(scanner)
		w := getNextInt(scanner)
		if h == 0 {
			break
		}
		grid := makeGrid(h, w)
		a := [2]int{}
		b := [2]int{}
		for i := 0; i < h; i++ {
			s := getNextString(scanner)
			for j := 0; j < w; j++ {
				if s[j] == '#' {
					grid[i][j] = math.MaxInt32
					continue
				}
				if s[j] == 'A' {
					a[0] = i
					a[1] = j
					continue
				}
				if s[j] == 'B' {
					b[0] = i
					b[1] = j
				}
				grid[i][j] = math.MaxInt32 - 1
			}
		}
		q := make([][2]int, 0)
		q = append(q, a)
		for len(q) > 0 {
			p := q[0]
			q = q[1:]
			for i := 0; i < 4; i++ {
				yy := p[0] + dy[i]
				xx := p[1] + dx[i]
				if yy == a[0] && xx == a[1] {
					continue
				}
				if yy < 0 || yy >= h {
					continue
				}
				if xx < 0 || xx >= w {
					continue
				}
				if grid[yy][xx] == math.MaxInt32 {
					continue
				}
				if grid[yy][xx] <= grid[p[0]][p[1]]+1 {
					continue
				}
				grid[yy][xx] = grid[p[0]][p[1]] + 1
				q = append(q, [2]int{yy, xx})
			}
		}
		move := getNextString(scanner)
		i := 0
		m := len(move)
		for {
			if i > 400 {
				fmt.Fprintln(writer, "impossible")
				break
			}
			if grid[b[0]][b[1]] <= i {
				fmt.Fprintln(writer, fmt.Sprintf("%d %d %d", i, b[0], b[1]))
				break
			}
			switch move[i%m] {
			case '8':
				if b[0] > 0 {
					b[0]--
				}
			case '6':
				if b[1]+1 < w {
					b[1]++
				}
			case '4':
				if b[1] > 0 {
					b[1]--
				}
			case '2':
				if b[0]+1 < h {
					b[0]++
				}
			}
			i++
		}
	}
}
func makeGrid(h, w int) [][]int {
	index := make([][]int, h, h)
	data := make([]int, h*w, h*w)
	for i := 0; i < h; i++ {
		index[i] = data[i*w : (i+1)*w]
	}
	return index
}

C++: #include <iostream>
#include <queue>
#include <cstring>

using namespace std;

#define MAX 20
#define INF 1e9

int H,W,ax,ay,bx,by;
char field[MAX][MAX];
string str;
const int dx[] = {-1,0,0,1,0};
const int dy[] = {0,-1,1,0,0};

struct State{
  int sx,sy,gx,gy;
  State(int sx,int sy,int gx,int gy) : sx(sx),sy(sy),gx(gx),gy(gy) {}
};

bool inField(int y,int x){
  return 0 <= y && y < H && 0 <= x && x < W;
}

int getDir(char ch){
  if(ch == '4') return 0;
  if(ch == '8') return 1;
  if(ch == '2') return 2;
  if(ch == '6') return 3;
  return 4;
}

void bfs(){
  int size = str.size();
  bool visited[MAX][MAX][MAX][MAX][MAX];
  memset(visited,0,sizeof(visited));
  visited[ay][ax][by][bx][0] = true;
  queue<State> Q;
  queue<int> Count;
  Q.push(State(ax,ay,bx,by));
  Count.push(0);
  while(!Q.empty()){
    State s = Q.front(); Q.pop();
    int cnt = Count.front(); Count.pop();

    if(s.sx == s.gx && s.sy == s.gy){
      cout << cnt << " " << s.sy << " " << s.sx << endl;
      return;
    }

    int dir = getDir(str[cnt%size]);
    int Gx = s.gx + dx[dir], Gy = s.gy + dy[dir];
    if(!inField(Gy,Gx)) Gx = s.gx, Gy = s.gy;

    for(int i = 0 ; i < 5 ; i++){
      int nx = s.sx + dx[i], ny = s.sy + dy[i];
      if(!inField(ny,nx)) continue;
      if(field[ny][nx] == '#') continue;
      if(visited[ny][nx][Gy][Gx][(cnt+1)%size]) continue;
      visited[ny][nx][Gy][Gx][(cnt+1)%size] = true;
      Q.push(State(nx,ny,Gx,Gy));
      Count.push(cnt+1);
    }
  }
  cout << "impossible" << endl;
}

int main(){
  while(cin >> H >> W, (H|W)){
    for(int i = 0 ; i < H ; i++){
      for(int j = 0 ; j < W ; j++){
        cin >> field[i][j];
        if(field[i][j] == 'A'){
          ax = j, ay = i;
        }else if(field[i][j] == 'B'){
          bx = j, by = i;
        }
      }
    }
    cin >> str;
    bfs();
  }

  return 0;
}

C++: #include<bits/stdc++.h>
#define rep(i,n)for(int i=0;i<(n);i++)
using namespace std;
typedef pair<int, int>P;

char s[20][21];
int d[20][20];
int dx[]{ 0,-1,0,0,1 }, dy[]{ 0,0,1,-1,0 };

int main() {
	int h, w;
	while (scanf("%d%d", &h, &w), h) {
		int ax, ay, bx, by;
		rep(i, h) {
			scanf("%s", s[i]);
			rep(j, w) {
				if (s[i][j] == 'A')ax = i, ay = j;
				if (s[i][j] == 'B')bx = i, by = j;
			}
		}
		string p; cin >> p;
		for (char&c : p) {
			if (c == '5')c = 0;
			if (c == '8')c = 1;
			if (c == '6')c = 2;
			if (c == '4')c = 3;
			if (c == '2')c = 4;
		}
		queue<P>que;
		memset(d, -1, sizeof(d));
		d[0][0] = 0; que.push(P(ax, ay));
		while (!que.empty()) {
			P p = que.front(); que.pop();
			for (int i = 1; i <= 4; i++) {
				int nx = p.first + dx[i], ny = p.second + dy[i];
				if (0 <= nx&&nx < h && 0 <= ny&&ny < w&&s[nx][ny] != '#'&&d[nx][ny] == -1) {
					d[nx][ny] = d[p.first][p.second] + 1;
					que.push(P(nx, ny));
				}
			}
		}
		int x = bx, y = by;
		int t = 0;
		rep(i, 10000000) {
			for (char c : p) {
				if (d[x][y] != -1 && d[x][y] <= t) {
					printf("%d %d %d\n", t, x, y); goto g;
				}
				int nx = x + dx[c], ny = y + dy[c]; t++;
				if (0 <= nx&&nx < h && 0 <= ny&&ny < w)x = nx, y = ny;
			}
		}
		puts("impossible");
	g:;
	}
}