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>
using namespace std;
typedef pair<pair<int,int>,int> pa;
#define ff first.first
#define fs first.second
#define f(a,b) for(int a=0;a<b;a++)

int h,w,x,y,sx,sy,gx,gy,i,j,g,m = 999999;
int dx[4]={1,0,-1,0};
int c[20][20];
char n[20][20];
string pat;

int main(){
    while(cin>>h>>w,h){
        f(i,h)f(j,w){
                c[i][j]=m;
                cin>>n[i][j];
                if(n[i][j]=='A')
                    sx=j,sy=i;
                else if(n[i][j]=='B')
                    gx=j,gy=i;
            }
        queue<pa>q;
        q.push(make_pair(make_pair(sx, sy), 0));
        while(q.size()){
            pa p = q.front();
            q.pop();
            if(c[p.fs][p.ff]!=m)
                continue;
            c[p.fs][p.ff]=p.second;
            f(i,4){
                x=p.ff+dx[i];
                y=p.fs+dx[(i+1)%4];
                if(x>=0&&x<w&&y>=0&y<h&&n[y][x]!='#'&&c[y][x]==m)
                    q.push(make_pair(make_pair(x, y), p.second+1));
            }
        }
        cin>>pat;
        g=0;
        f(j,m){
            i=j%pat.length();
            if(c[gy][gx]<=g){
                cout<<g<<" "<<gy<<" "<<gx<<endl;
                break;
            }
            if(g>700){
                cout<<"impossible"<<endl;
                break;
            }
            if(pat[i]=='8')
                gy--;
            else if(pat[i]=='6')
                gx++;
            else if(pat[i]=='4')
                gx--;
            else if(pat[i]=='2')
                gy++;
            gy=max(0,min(h-1,gy));
            gx=max(0,min(w-1,gx));
            g++;
        }
    }
}

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

const int INF = 1 << 30;
const int dx[] = {0, 1, 0, -1, 0};
const int dy[] = {0, 0, 1, 0, -1};

class State
{
public:
  int sx, sy, gx, gy, time;
  State(int _sx, int _sy, int _gx, int _gy, int _time)
    :sx(_sx), sy(_sy), gx(_gx), gy(_gy), time(_time) {}
};

int main()
{
  int H, W;
  while (cin >> H >> W) {
    if ((H|W) == 0)
      break;

    vector<string> city(H);
    int sx, sy, gx, gy;
    for (int i = 0; i < H; ++i) {
      cin >> city[i];

      if (city[i].find_first_of("A") != string::npos) {
	sy = i;
	sx = city[i].find_first_of("A");
	city[sy][sx] = '.';
      }
      if (city[i].find_first_of("B") != string::npos) {
	gy = i;
	gx = city[i].find_first_of("B");
	city[gy][gx] = '.';
      }
    }

    string pattern;
    cin >> pattern;
    for (int i = 0; i < pattern.size(); ++i) {
      if (pattern[i] == '5')
	pattern[i] = '0';
      else if (pattern[i] == '8')
	pattern[i] = '4';
      else if (pattern[i] == '6')
	pattern[i] = '1';
      else if (pattern[i] == '4')
	pattern[i] = '3';
      else
	pattern[i] = '2';
    }

    bool found = false;
    queue<State> que;
    que.push(State(sx, sy, gx, gy, 0));
    vector<vector<vector<vector<vector<int> > > > > dp(H, vector<vector<vector<vector<int> > > >(W, vector<vector<vector<int> > >(H, vector<vector<int > >(W, vector<int>(pattern.size(), INF)))));
    while (!que.empty()) {
      const State st = que.front();
      que.pop();

      if(st.sx == st.gx && st.sy == st.gy) {
	cout << st.time << " " << st.sy << " " << st.sx << endl;
	found = true;
	break;
      }

      if (dp[st.sy][st.sx][st.gy][st.gx][st.time%pattern.size()] < st.time)
	continue;
      dp[st.sy][st.sx][st.gy][st.gx][st.time%pattern.size()] = st.time;

      for (int d = 0; d < 5; ++d) {
	sx = st.sx + dx[d];
	sy = st.sy + dy[d];
	gx = st.gx + dx[pattern[st.time%pattern.size()]-'0'];
	gy = st.gy + dy[pattern[st.time%pattern.size()]-'0'];

	if (sx < 0 || W <= sx || sy < 0 || H <= sy || city[sy][sx] == '#')
	  continue;

	if (gx < 0 || W <= gx)
	  gx = st.gx;
	if (gy < 0 || H <= gy)
	  gy = st.gy;

	if (dp[sy][sx][gy][gx][(st.time+1)%pattern.size()] > st.time+1)
	  que.push(State(sx, sy, gx, gy, st.time+1));
      }

    }

    if (!found)
      cout << "impossible" << endl;
  }
  return 0;
}