using System; using System.Collections.Generic; using System.Collections; using System.Collections.Specialized; using System.Linq; using System.Text; using System.IO; using System.Reflection; using static System.Math; using System.Numerics; static class Program{ const int mod=(int)1e9+7; static readonly int[][] di1=new int[][]{new int[]{-1,0},new int[]{1,0},new int[]{0,-1},new int[]{0,1}}; static readonly int[][] di2=new int[][]{new int[]{-1,-1},new int[]{-1,0},new int[]{-1,1},new int[]{0,-1},new int[]{0,1},new int[]{1,-1},new int[]{1,0},new int[]{1,1}}; static char[][] bm; static int[][] b; static void Main(){ Sc sc=new Sc(); var s=sc.Ia; int h=s[0],w=s[1]; char c='#'; var a=sc.Ia; var z=sc.Ia; bm=new char[h+2][]; b=new int[h+2][]; var qu=new Queue>(); for(int i = 1;i<=h;i++) { bm[i]=(c+sc.S+c).ToCharArray(); b[i]=new int[w+2]; for(int j = 0;j0){ var e=qu.Dequeue(); Fdi(e.Item1,e.Item2,(y,x)=>{ if(bm[y][x]=='.'&&b[y][x]==0){ qu.Enqueue(Tuple.Create(y,x,e.Item3+1)); b[y][x]=e.Item3+1; } }); } Console.WriteLine("{0}",b[z[0]][z[1]]-1); } static void Fdi(int y,int x,Action f){for(int i=0;i<4;i++){f(y+di1[i][0],x+di1[i][1]);}} } public class Sc{ public int I{get{return int.Parse(Console.ReadLine());}} public long L{get{return long.Parse(Console.ReadLine());}} public double D{get{return double.Parse(Console.ReadLine());}} public string S{get{return Console.ReadLine();}} public int[] Ia{get{return Array.ConvertAll(Console.ReadLine().Split(),int.Parse);}} public long[] La{get{return Array.ConvertAll(Console.ReadLine().Split(),long.Parse);}} public double[] Da{get{return Array.ConvertAll(Console.ReadLine().Split(),double.Parse);}} public string[] Sa{get{return Console.ReadLine().Split();}} public object[] Oa{get{return Console.ReadLine().Split();}} public int[] Ia2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),int.Parse);}} public int[] Ia3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),int.Parse);} public int[] Ia3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),int.Parse);} public long[] La2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),long.Parse);}} public long[] La3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),long.Parse);} public long[] La3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),long.Parse);} public double[] Da2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),double.Parse);}} public double[] Da3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),double.Parse);} public double[] Da3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),double.Parse);} public T[] Arr(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i