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 <set>
#include <cstring>
#include <cstdio>
#include <queue>
#define REP(i,n) for(int i=0; i<(int)(n); i++)

inline int getInt(){ int s; scanf("%d", &s); return s; }

#define IN(x,s,g) ((x) >= (s) && (x) < (g))
#define ISIN(x,y,w,h) (IN((x),0,(w)) && IN((y),0,(h)))

using namespace std;

char g[25][25];
int memo[25][25][25][25][15];
char pat[15];

int dx[10] = {
  0, 0, 0, 0, -1, 0, 1, 0, 0, 0
};
int dy[10] = {
  0, 0, 1, 0, 0, 0, 0, 0, -1, 0
};

const int _dx[] = {0,1,0,-1,0};
const int _dy[] = {-1,0,1,0,0};

struct data{
  int x1, y1, x2, y2;
  int p;
};

int main(){
  while(true){
    int h = getInt();
    int w = getInt();
    int len;
    int x1, x2, y1, y2;
    queue<data> que;
    bool ok = false;

    if(h + w == 0) break;
    REP(i,h) scanf("%s", g[i]);
    REP(i,h) REP(j,w){
      if(g[i][j] == 'A'){
        x1 = j; y1 = i;
        g[i][j] = '.';
      }else if(g[i][j] == 'B'){
        x2 = j; y2 = i;
        g[i][j] = '.';
      }
    }

    scanf("%s", pat);
    len = strlen(pat);

    memset(memo, -1, sizeof(memo));
    que.push((data){x1,y1,x2,y2,0});
    memo[y1][x1][y2][x2][0] = 0;

    while(que.size()){
      data d = que.front(); que.pop();
      int x1 = d.x1;
      int y1 = d.y1;
      int x2 = d.x2;
      int y2 = d.y2;
      int p  = d.p;
      int t  = memo[y1][x1][y2][x2][p];

      if(x1 == x2 && y1 == y2){
        ok = true;
        printf("%d %d %d\n", t, y1, x1);
        break;
      }

      REP(i,5){
        int xx1 = x1 + _dx[i];
        int yy1 = y1 + _dy[i];

        int xx2 = x2 + dx[pat[p] - '0'];
        int yy2 = y2 + dy[pat[p] - '0'];
        int pp  = (p + 1) % len;

        if(!ISIN(xx2,yy2,w,h)){
          xx2 = x2;
          yy2 = y2;
        }

        if(ISIN(xx1,yy1,w,h) && memo[yy1][xx1][yy2][xx2][pp] == -1 &&
           g[yy1][xx1] == '.'){

          memo[yy1][xx1][yy2][xx2][pp] = t + 1;
          que.push((data){xx1,yy1,xx2,yy2,pp});
        }
      }
    }

    if(!ok) puts("impossible");
  }

  return 0;
}

C++: #include<iostream>
#include<queue>
using namespace std;
typedef pair<pair<int,int>,int> pa;
#define ff first.first
#define fs first.second
#define mp(a,b,c) make_pair(make_pair(a,b),c)

int h,w,sx,sy,gx,gy,m=9999;
int dx[4]={1,0,-1,0};
int dy[4]={0,-1,0,1};
int co[21][21];
char ma[21][21];
bool visited[21][21];
string pat;

int main(){
    while(cin>>h>>w,h){
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                co[i][j]=m;
                cin>>ma[i][j];
                if(ma[i][j]=='A')
                    sx=j,sy=i;
                else if(ma[i][j]=='B')
                    gx=j,gy=i;
            }
        }
        queue<pa>q;
        q.push(mp(sx, sy, 0));
        while(q.size()){
            pa p = q.front();
            q.pop();
            if(co[p.fs][p.ff]!=m)
                continue;
            co[p.fs][p.ff]=p.second;
            for(int i=0;i<4;i++){
                int nx=p.ff+dx[i];
                int ny=p.fs+dy[i];
                if(nx>=0&&nx<w&&ny>=0&ny<h&&ma[ny][nx]!='#'&&co[ny][nx]==m)
                    q.push(mp(nx, ny, p.second+1));
            }
        }
        cin>>pat;
        for(int j=0,go=0;int i=j%pat.length();j++,go++){
            if(co[gy][gx]<=go){
                cout<<go<<" "<<gy<<" "<<gx<<endl;
                break;
            }
            if(go>10000){
                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++: #import<stdio.h>
#import<queue>
int main(){std::queue<int>q;int w,h,f[484],i,j,a,b,t,x,z;char p[15];for(;scanf("%d%d ",&h,&w),h;){for(i=0;i++<h;f[i*22]=f[i*22-~w]=-1,getchar())for(j=0;j++<w;z-35?z>65?b=x:z>64?a=x:1:--f[x])f[j]=f[j-~h*22]=-1,f[x=i*22+j]=-2,z=getchar();f[a]=t=0;q.push(0);for(q.push(a);a=q.front(),q.size()>1;q.pop())if(!a)++t,q.push(0);else for(i=4;i--;)if(f[x=a+" 57L"[i]-54]==-2)f[x]=t,q.push(x);q.pop();scanf("%s",p);for(a=t=0;!a;){x=b;z=0;for(i=0;!a&&p[i];f[b]>=0&&++z)++t,~f[j=b-54+"L65676 "[p[i++]-50]]?b=j:0,f[b]>=0&t>=f[b]?a=b:0;!z&!a&!p[i]&b==x&f[b]<0&&--a;}printf(~a?"%d %d %d\n":"impossible\n",t,a/22-1,a%22-1);}}