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(i=a;i<b;i++)

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

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;
        }
        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;
        for(j=0,go=0;;j++,go++){
            i=j%pat.length();
            if(c[gy][gx]<=go){
                cout<<go<<" "<<gy<<" "<<gx<<endl;
                break;
            }
            if(go>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));
        }
    }
}

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

#define MAX 20
#define PMAX 10
#define rep(i, n) for ( int i = 0; i < (int)n; i++ )
#define INFTY (1<<21)

struct State{ int a, b, cur; };

int H, W;
string P;
char G[MAX][MAX];

int getDi( char ch ){
    if ( ch == '5' || ch == '4' || ch == '6') return 0;
    else if ( ch == '2' ) return 1;
    else if ( ch == '8' ) return -1;
}

int getDj( char ch ){
    if ( ch == '5' || ch == '2' || ch == '8') return 0;
    else if ( ch == '6' ) return 1;
    else if ( ch == '4' ) return -1;
}

int bfs(int as, int bs, int &g){
    int D[MAX*MAX][MAX*MAX][PMAX];
    rep(i, H*W) rep(j, H*W) rep(k, P.size()) {
	D[i][j][k] = INFTY;
    }
    State s;
    s.a = as;
    s.b = bs;
    s.cur = 0;
    queue<State> Q;

    Q.push(s);
    D[s.a][s.b][s.cur] = 0;

    static const int di[5] = {0, 0, -1, 0, 1};
    static const int dj[5] = {0, 1, 0, -1, 0};

    State u, v;
    while( !Q.empty() ){
	u = Q.front(); Q.pop();
	if ( u.a == u.b ) {
	    g = u.a;
	    return D[u.a][u.b][u.cur];
	}
	
	int ni, nj;
	for ( int r = 0; r < 5; r++ ){
	    ni = u.a/W + di[r];
	    nj = u.a%W + dj[r];
	    if ( ni < 0 || nj < 0 || ni >= H || nj >= W ) continue;
	    if ( G[ni][nj] == '#' ) continue;

	    v = u;
	    v.a = ni*W + nj;

	    ni = v.b/W + getDi(P[v.cur]);
	    nj = v.b%W + getDj(P[v.cur]);
	    
	    if ( ni < 0 || nj < 0 || ni >= H || nj >= W ){
		ni = v.b/W;
		nj = v.b%W;
	    }

	    v.cur = (v.cur+1)%P.size();
	    v.b = ni*W + nj;
	    
	    if ( D[v.a][v.b][v.cur] == INFTY ){
		D[v.a][v.b][v.cur] = D[u.a][u.b][u.cur] + 1;
		Q.push(v);
	    }
	}
    }

    return INFTY;
}

main(){
    while( cin >> H >> W && H && W ){	
	int s, g, p;
	rep(i, H) rep(j, W) {
	    cin >> G[i][j];
	    if ( G[i][j] == 'A' ){ G[i][j] = '.'; s = i*W+j; }
	    if ( G[i][j] == 'B' ){ G[i][j] = '.'; p = i*W+j; }
	}
	cin >> P;
	int cost = bfs(s, p, g);
	if ( cost == INFTY ) cout << "impossible" << endl;
	else cout << cost << " " << g/W << " " << g%W << endl;
    }
}