// Slower C++ solution:
#include "cstring"

#include "cstdio"

#include "queue"

using namespace std;



const int maxn=1024;



int dx[4]={0,0,1,-1};

int dy[4]={1,-1,0,0};



char mp[maxn][maxn];

int vis[maxn][maxn];

int wx[10],wy[10];

int n,m,k;



int bfs(int x1,int y1,int x2,int y2)

{

	memset(vis,0,sizeof(vis));

	queue<int>qx;qx.push(x1);

	queue<int>qy;qy.push(y1);

	queue<int>qt;qt.push(0);

	vis[x1][y1]=1;

	

	while(!qx.empty())

	{

		int nx=qx.front();qx.pop();

		int ny=qy.front();qy.pop();

		int nt=qt.front();qt.pop();

		

		if(nx==x2 && ny==y2)return nt;

		

		for(int i=0;i<4;i++)

		{

			int px=nx+dx[i];

			int py=ny+dy[i];

			if(px>=0 && py>=0 && px<n && py<m && mp[px][py]!='X' && !vis[px][py])

			{

				qx.push(px);

				qy.push(py);

				qt.push(nt+1);

				vis[px][py]=1;

			}

		}

		

	}

	

	return 0;

}



int main()

{

	//freopen("f.txt","r",stdin);

	scanf("%d%d%d",&n,&m,&k);

	for(int i=0;i<n;i++)

		for(int j=0;j<m;j++)

		{

			mp[i][j]=getchar();

			while(mp[i][j]=='\n' || mp[i][j]=='\0')mp[i][j]=getchar();

			if(mp[i][j]>='1' && mp[i][j]<='9')

			{

				wx[mp[i][j]-'0']=i;

				wy[mp[i][j]-'0']=j;

			}

			if(mp[i][j]=='S')

			{

				wx[0]=i;

				wy[0]=j;

			}	

		}

	int ans=0;

	for(int i=0;i<k;i++)

		ans+=bfs(wx[i],wy[i],wx[i+1],wy[i+1]);

	printf("%d\n",ans);

	return 0;

} 


// Faster C++ solution for the same problem (measured speedup: 2.559239050735839x):
#include <iostream>

#include <cstring>

#include <cstdio>

#include <algorithm>

#include <vector>

#include <queue>



using namespace std;

struct as

{

    int x,y;

}pos[10]; //用来存储每次的起点和终点

struct node

{

    int x,y;

    int step;

};

bool vis[1010][1010];

char maze[1050][1050];

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

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

int H,W,N;



bool check(int x,int y)

{

    if (x<=0 || x>H) return 1;

    if (y<=0 || y>W) return 1;

    if (vis[x][y]) return 1;

    if (maze[x][y] =='X')return 1;

    return 0;

}

int bfs(int m,int n)

{

    memset(vis,0,sizeof vis);

    int sx = pos[m].x, sy = pos[m].y;

    int gx = pos[n].x, gy = pos[n].y;

   // printf("%d %d\n",sx,sy);

   // printf("%d %d\n",gx,gy);

    queue<node> Q;

    node a,next;

    a.step = 0;

    a.x = sx, a.y =sy;

    Q.push(a);

    while(!Q.empty())

    {

        a = Q.front();

        Q.pop();

        if (a.x == gx && a.y == gy)

            return a.step;

        for(int i = 0; i < 4 ;i++)

        {

            int nx = a.x + dx[i];

            int ny = a.y + dy[i];

            if(check(nx,ny))

                continue;

            else

            {

                vis[nx][ny] =1;

                next.x = nx,next.y = ny,next.step = a.step+1;

                Q.push(next);

            }

        }

    }

    return 999999;

}



int main()

{

   // freopen("in.txt","r",stdin);

    while(cin>>H>>W>>N)

    {

        int sx,sy;

        for(int i = 1;i<=H;i++)

        {

            for(int j = 1; j <= W;j++)

            {

                cin>>maze[i][j];

                if (maze[i][j] >='1' && maze[i][j]<='9')

                {

                    pos[maze[i][j]-'0'].x = i;

                    pos[maze[i][j]-'0'].y = j;

                }

                if (maze[i][j]=='S')

                    sx=i,sy = j;

            }

        }



        pos[0].x = sx,pos[0].y = sy;

        int ans = 0;

        for(int i = 0;i<N;i++)

            ans += bfs(i,i+1);

        cout<<ans<<endl;

    }

    return 0;

}