// Slower C++ solution:
#include <queue>

#include <cstring>

#include <iostream>

using namespace std;



const int N = 1111;

const int cx[] = {0, 0, 1, -1}, cy[] = {1, -1, 0, 0};

char maze[N][N];

int step[N][N];

int h, w, n, sx, sy, ans;



int bfs(int cheese){

    memset(step, -1, sizeof(step));

    queue<pair<int, int> > que;

    que.push(make_pair(sx, sy));

    step[sx][sy] = 0;

    while(!que.empty()){

        int x = que.front().first, y = que.front().second;

        que.pop();

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

            int nx = x + cx[i], ny = y + cy[i];

            if(nx < 0 || h <= nx || ny < 0 || w <= ny || maze[nx][ny] == 'X' || step[nx][ny] != -1) continue;

            step[nx][ny] = step[x][y] + 1;

            if(maze[nx][ny] - '0' == cheese){

                sx = nx;

                sy = ny;

                return step[nx][ny];

            }

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

        }

    }

    return 0;

}



int main(){

    ios::sync_with_stdio(false);

    cin.tie(NULL);

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

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

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

                cin >> maze[i][j];

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

                    sx = i;

                    sy = j;

                }

            }

        ans = 0;

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

            ans += bfs(i);

        cout << ans << endl;

    }

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 2.997985978665258x):
#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;

}