// Slower C++ solution:
#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;

}




// Faster C++ solution for the same problem (measured speedup: 2.014089777899365x):
#include<iostream>

#include<queue>

#include<algorithm>

using namespace std;



typedef pair<int,int> P;



const int inf=10000;

const int maxh=1010;

const int maxw=1010;

const int maxn=9;



int h,w,n;

int d[maxh][maxw];

char m[maxh][maxw];



int bx,by;

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

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



int bfs(char c){

	for(int i=0;i<h;i++){

		fill(d[i],d[i]+w,inf);

	}

	d[bx][by]=0;

	queue<P> que;

	que.push(P(bx,by));

	while(!que.empty()){

		P p=que.front();

		que.pop();

		if(m[p.first][p.second]==c){

			bx=p.first,by=p.second;

			break;

		}

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

			int nx=p.first+dx[i];

			int ny=p.second+dy[i];

			if(0<=nx && nx<h && 0<=ny && ny<w && m[nx][ny]!='X' && d[nx][ny]==inf){

				que.push(P(nx,ny));

				d[nx][ny]=d[p.first][p.second]+1;

			}

		}

	}

	return d[bx][by];

}



void solve(){

	for(int i=0;i<h;i++){

		for(int j=0;j<w;j++){

			if(m[i][j]=='S'){

				bx=i,by=j;

				break;

			}

		}

	}

	int ans=0;

	for(int i=1;i<=n;i++){

		ans+=bfs('0'+i);

	}

	cout<<ans<<endl;

}



int main(){

	while(cin>>h>>w>>n){

		for(int i=0;i<h;i++){

			cin>>m[i];

		}

		solve();

	}

	return 0;

}