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

int h,w,sx,sy,gx,gy;
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]=INT_MAX;
                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(make_pair(make_pair(sx, sy), 0));
        while(q.size()){
            pa p = q.front();
            q.pop();
            if(co[p.fs][p.ff]!=INT_MAX)
                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]==INT_MAX)
                    q.push(make_pair(make_pair(nx, ny), p.second+1));
            }
        }
        cin>>pat;
        for(int j=0,go=0;;j++,go++){
            int i=j%pat.length();
            if(co[gy][gx]<=go){
                cout<<go<<" "<<gy<<" "<<gx<<endl;
                break;
            }
            if(go>100000){
                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<stdio.h>
#include<queue>
int main(){
	std::queue<int> q;
	int w,h,f[484],i,j,d[]={22,0,-1,0,1,0,-22},a,b,t,x,z;
	char p[15];
	for(;scanf("%d%d ",&h,&w),h;){
		for(j=0;j<w+2;j++)f[j]=f[j-~h*22]=-9;
		for(i=1;i<=h;i++){
			for(j=1;j<=w;j++){
				f[x=i*22+j]=-1;
				switch(getchar()){
					case'#':--f[x];break;
					case'A':a=x;break;
					case'B':b=x;break;
				}
			}
			f[i*22]=f[i*22-~w]=-9;
			getchar();
		}
		
		f[a]=t=0;
		q.push(0);
		for(q.push(a);q.size()>1;){
			a=q.front();
			q.pop();
			if(a){
				for(i=0;i<7;i+=2)
					if(f[x=a+d[i]]==-1)
						f[x]=t,
						q.push(x);
			else
				++t,q.push(0);
		}
		q.pop();
		scanf("%s",p);
		for(a=t=0;!a;){
			x=b;
			z=0;
			for(i=0;!a&&p[i];i++){
				t++;
				f[j=b+d[p[i]-'2']]>-3?b=j:0;
				f[b]>=0&&t>=f[b]?a=b:0;
				f[b]>=0&&++z;
			}
			!z&!a&!p[i]&b==x&f[b]<0&&--a;
		}
		printf(a<0?"impossible\n":"%d %d %d\n",t,a/22-1,a%22-1);
	}
}

C++: #include<iostream>
#include<algorithm>
#include<climits>
#include<vector>
#include<queue>
#include<stack>
#include<cmath>
#include<string.h>

using namespace std;

int h,w,sx,sy,gx,gy;
int dx[4]={1,0,-1,0};
int dy[4]={0,-1,0,1};

char ma[21][21];
int co[21][21];
bool visited[21][21];

int main(){
    while(cin>>h>>w,h){
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                co[i][j]=INT_MAX;
                cin>>ma[i][j];
                if(ma[i][j]=='A'){
                    sx=j,sy=i;
                } else if(ma[i][j]=='B'){
                    gx=j,gy=i;
                }
            }
        }
        memset(visited, 0, sizeof(visited));
        queue<pair<pair<int,int>,int> >q;
        q.push(make_pair(make_pair(sx, sy), 0));
        while(q.size()){
            pair<pair<int,int>,int> p = q.front();
            visited[p.first.second][p.first.first]=1;
            co[p.first.second][p.first.first]=p.second;
           // cout<<p.first.second<<"  "<<p.first.first<<"  "<<p.second<<endl;
            q.pop();
            for(int i=0;i<4;i++){
                int nx=p.first.first+dx[i];
                int ny=p.first.second+dy[i];
                if(nx>=0&&nx<w&&ny>=0&ny<h&&ma[ny][nx]!='#'&&co[ny][nx]==INT_MAX&&ma[ny][nx]!='A'&&!visited[ny][nx]){
                    q.push(make_pair(make_pair(nx, ny), p.second+1));
                }
            }
        }
        string pat;
        cin>>pat;
        int go=0;
        for(int j=0;;j++){
            int i=j%pat.length();
         //   cout<<gy<<" "<<gx<<" "<<co[gy][gx]<<" "<<INT_MAX<<endl;
            if(co[gy][gx]<=go){
                cout<<go<<" "<<gy<<" "<<gx<<endl;
                break;
            }
            if(go>1000){
                cout<<"impossible"<<endl;
                break;
            }
            if(pat[i]=='5'){
                
            } else 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,gy);
            gy=min(h-1,gy);
            gx=max(0,gx);
            gx=min(w-1,gx);
            go++;
        }
    }
}