// 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: 4.880058894593779x):
#include <iostream>

#include <queue>

#include <string>



using namespace std;



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

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

int First = 1000;

int w,h,n;

int ans = 0;

int d[1001][1001];

typedef struct p{

	int x, y;

}P;

string mapp[1001];

P nezumi[11];





//幅優先探索を行う

void bfs(){

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

		P sp = nezumi[i-1];

		int sx = nezumi[i-1].x;

		int sy = nezumi[i-1].y;

		int gx = nezumi[i].x;

		int gy = nezumi[i].y;



		//二次元配列の初期化をする

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

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

				d[y][x] = First;

			}

		}

		

		queue<P> q;

		q.push( sp );

		d[sy][sx] = 0;

		while( !q.empty() ){

			P now = q.front();

			q.pop();

			int x = now.x;

			int y = now.y;



			if( x == gx && y == gy ){

				ans += d[gy][gx];



				/*動作確認

				cout << "\n";

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

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

						if (d[y][x]==First){cout << "X";}

							else{cout << d[y][x];}

					}

					cout << "\n";

				}*/

				break;

			}



			//redandblackと同じように探索

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

				int newx = x + dx[i];

				int newy = y + dy[i];

				if( newx < 0 || newy < 0 || newx >= w || newy >= h ) continue;

				if( mapp[newy][newx] != 'X' ){

					P next;

					next.x = newx;

					next.y = newy;

					if( d[newy][newx] == First ){

						d[newy][newx] = d[y][x] + 1;

						q.push( next );

					}

				}

			}

		}

	}

}



int main(){

	//標準入力

	cin >> h >> w >> n;

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

		cin >> mapp[y];

	}

	

	//スタートと数字の確認

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

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

			char c = mapp[y][x];



			//アスキー使っていい感じにしてみる

			if( c >= '1' && c <= '9' ){

				nezumi[ c - '0' ].x = x;

				nezumi[ c - '0' ].y = y;

			}

			if(c == 'S'){

				nezumi[0].x = x;

				nezumi[0].y = y;

			}

		}

	}

	bfs();

	cout << ans << endl;

}