// Slower C++ solution:
#include<stdio.h>

#include<string.h>

#include<algorithm>

#include<queue>



using namespace std;



struct node

{

    int s;

    int x,y;

};



int dir[][2] = {0,1,1,0,0,-1,-1,0};

int vis[1010][1010];

int n,m,k,sx[20],sy[20];

char mp[1010][1010];



int bfs(int x,int y,int ex,int ey)

{

    queue<node> q;

    node a,b,d;

    a.x = x;

    a.y = y;

    a.s = 0;

    vis[x][y] = 1;

    q.push(a);

    while(!q.empty())

    {

        b = q.front();

        q.pop();

        if(b.x == ex && b.y == ey)

        {

            return b.s;

        }

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

        {

            d.x = b.x + dir[i][0];

            d.y = b.y + dir[i][1];

            if(d.x >= 0 && d.x < n && d.y >= 0 && d.y < m && vis[d.x][d.y] == 0)

            {

                if(mp[d.x][d.y] >= '1' && mp[d.x][d.y] <= '9' || mp[d.x][d.y] == '.')

                {

                    vis[d.x][d.y] = 1;

                    d.s = b.s + 1;

                    q.push(d);

                }

            }

        }

    }

}



int main()

{

    while(~scanf("%d%d%d",&n,&m,&k))

    {

        int i,j,t;



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

        {

            scanf("%s",mp[i]);

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

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

                {

                    sx[0] = i;

                    sy[0] = j;

                    mp[i][j] = '.';

                }

        }

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

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

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

                {

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

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

                }

        int ans = 0;

        for(i = 1; i <= k; i++)

        {

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

            ans += bfs(sx[i-1],sy[i-1],sx[i],sy[i]);

        }

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

    }

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 2.4955958944033374x):
#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;

}