/* Tue Mar 16 17:41:16 JST 2004 */
#include <stdio.h>
#include <limits.h>

#define WALL 0
#define EMPTY 1
#define START 2
#define HOLE 3
#define FOOD 4

int w, h;
int area[10][10];
int distance[10][10][10];

int main()
{
  int i, j, k, d, x, y, hp;
  int dx[4] = {0, 1, 0, -1};
  int dy[4] = {1, 0, -1, 0};
  int found;

  while (1) {
    scanf("%d %d", &w, &h); if (w == 0 && h == 0) { break; }
    for (i = 0; i <= h+1; i++) {
      for (j = 0; j <= w+1; j++) {
        if (i == 0 || j == 0 || i == h+1 || j == w+1) {
          area[i][j] = WALL;
          continue;
        }
        scanf("%d", &area[i][j]);
        for (hp = 0; hp < 7; hp++) {
          distance[i][j][hp] = INT_MAX;
        }
        if (area[i][j] == START) {
          distance[i][j][6] = 0;
          area[i][j] = EMPTY;
        }
      }
    }

    for (d = 0; ; d++) {
      found = 0;
      for (y = 1; y <= h; y++) {
        for (x = 1; x <= w; x++) {
          for (hp = 2; hp <= 6; hp++) {
            if (distance[y][x][hp] == d) {
              for (i = 0; i < 4; i++) {
                if (area[y+dy[i]][x+dx[i]] == FOOD) {
                  if (distance[y+dy[i]][x+dx[i]][6] > d + 1) {
                    found = 1;
                    distance[y+dy[i]][x+dx[i]][6] = d + 1;
                  }
                }
                if (area[y+dy[i]][x+dx[i]] == EMPTY) {
                  if (distance[y+dy[i]][x+dx[i]][hp-1] > d + 1) {
                    found = 1;
                    distance[y+dy[i]][x+dx[i]][hp-1] = d + 1;
                  }
                }
                if (area[y+dy[i]][x+dx[i]] == HOLE) {
                  found = 1;
                  goto quit;
                }
              }
            }
          }
        }
      }
      if (!found) { break; }
    }
  quit:

#if 0
    for (y = 1; y <= h; y++) {
      for (x = 1; x <= w; x++) {
        for (hp = 1; hp <= 6; hp++) {
          if (distance[y][x][hp] == INT_MAX) { printf("-,"); }
          else                               { printf("%d,", distance[y][x][hp]); }
        }
        printf(" ");
      }
      printf("\n");
    }
    printf("=====\n");
#endif


    if (found) {
      printf("%d\n", d+1);
    }
    else {
      printf("-1\n");
    }
  }
  return 0;
}
/* Tue Mar 16 18:31:47 JST 2004 */