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 <stdio.h>
#include <list>
#include <string.h>
#include <set>

using namespace std;

//#define DEBUG

typedef struct {
	int px, py;
	int gx, gy;
	int move_index;
	int depth;
} DATA;


char map[20 + 2][20 + 2];
char move_inst[11];
set<unsigned> lstHash;
list<DATA> lstSarch;

unsigned calc_hash(const DATA& data)
{
	unsigned hash;
	
	hash = data.px | (data.py << 5) | (data.gx << 10) | (data.gy << 15) | (data.move_index << 20);
	
	return (hash);
}

bool is_add(const DATA& data)
{
	unsigned hash;
	
	hash = calc_hash(data);
	if (map[data.px][data.py] == -1 || map[data.px][data.py] == '#' || lstHash.find(hash) != lstHash.end()){
		return (false);
	}
	
	return (true);
}

int width_priority_sarch(const DATA& data)
{
	DATA add;
	
	add.depth = data.depth + 1;
	add.move_index = (data.move_index + 1) % strlen(move_inst);
	
	add.gx = data.gx;
	add.gy = data.gy;
	switch (move_inst[data.move_index]){
	  case '8': add.gy--; break;
	  case '4': add.gx--; break;
	  case '6': add.gx++; break;
	  case '2': add.gy++; break;
	  default :           break;
	}
	
	if (map[add.gx][add.gy] == -1){
		add.gx = data.gx;
		add.gy = data.gy;
	}
	
	add.px = data.px;
	add.py = data.py;
	if (is_add(add) == true){
		lstSarch.push_back(add);
		lstHash.insert(calc_hash(add));
	}
#ifdef DEBUG
	printf("%d %d\n", add.move_index, data.move_index);
	printf("%u %u\n", calc_hash(add), calc_hash(data));
#endif
	
	add.px++;
	if (is_add(add) == true){
		lstSarch.push_back(add);
		lstHash.insert(calc_hash(add));
	}
	add.px = data.px;
	add.px--;
	if (is_add(add) == true){
		lstSarch.push_back(add);
		lstHash.insert(calc_hash(add));
	}
	add.px = data.px;
	add.py++;
	if (is_add(add) == true){
		lstSarch.push_back(add);
		lstHash.insert(calc_hash(add));
	}
	add.py = data.py;
	add.py--;
	if (is_add(add) == true){
		lstSarch.push_back(add);
		lstHash.insert(calc_hash(add));
	}
	
	return (0);
}

bool is_end(DATA& data)
{
	if (data.px == data.gx && data.py == data.gy){
		return (true);
	}
	return (false);
}

int main(void)
{
	DATA start;
	int hight, with;
	
	while (1){
		lstHash.clear();
		lstSarch.clear();
		
		scanf("%d%d", &hight, &with);
		
		if (hight == 0 || with == 0){
			break;
		}
		
		for (int i = 0; i < 22; i++){
			for (int j = 0; j < 22; j++){
				map[i][j] = -1;
			}
		}
		for (int y = 0; y < hight; y++){
			char str[21];
			scanf("%s", str);
			for (int x = 0; x < with; x++){
				map[x + 1][y + 1] = str[x];
				if (map[x + 1][y + 1] == 'A'){
					start.px = x + 1;
					start.py = y + 1;
					map[x + 1][y + 1] = '.';
				}
				if (map[x + 1][y + 1] == 'B'){
					start.gx = x + 1;
					start.gy = y + 1;
					map[x + 1][y + 1] = '.';
				}
			}
		}
		scanf("%s", move_inst);
		start.move_index = 0;
		start.depth = 0;
		
		lstHash.insert(calc_hash(start));
		lstSarch.push_back(start);
		
		while (lstSarch.empty() == false && is_end(lstSarch.front()) == false){
#ifdef DEBUG
			printf("%d %d %d %d %d %d\n", lstSarch.front().px, lstSarch.front().py, lstSarch.front().gx, lstSarch.front().gy, lstSarch.front().depth, lstSarch.front().move_index);
#endif
			width_priority_sarch(lstSarch.front());
			lstSarch.pop_front();
		}
		
		if (lstSarch.empty() == true){
			puts("impossible");
		}
		else {
			printf("%d %d %d\n", lstSarch.front().depth, lstSarch.front().py - 1, lstSarch.front().px - 1);
		}
	}
	
	return (0);
}