// Slower C++ solution:
#include"stdio.h"

#include"stdlib.h"

#include"string.h"

#include"algorithm"

#include"queue"

using namespace std;

struct mmm

{

	int x,y;

}vv;

int dir[4][2] = {0,-1,-1,0,0,1,1,0};

char xx[1005][1005];

int bb[11][2];

queue <mmm> qq;

int vis[1005][1005];

int bfs(char t)

{

	int sum = 0;

	int pl = 0;

	while(!qq.empty())

	{

		vv = qq.front();

		int x0 = vv.x;

		int y0 = vv.y;

		//printf("%d %d %d\n",x0,y0,vis[x0][y0]);

		qq.pop();

		if(xx[x0][y0] == t && !pl)

		{

			sum = vis[x0][y0];

			pl = 1;

		}

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

		{

			int xt = x0 + dir[i][0];

			int yt = y0 + dir[i][1];

			if(xx[xt][yt] != '#' && xx[xt][yt] != 'X' && vis[xt][yt] == -1)

			{

				vis[xt][yt] = vis[x0][y0] + 1;

				vv.x = xt;

				vv.y = yt;

				qq.push(vv);

			}

		}

	}

	return sum;

}

int main()

{

	int a,b,c,d,x1,y1,sum;

	while(~scanf("%d %d %d",&a,&b,&c))

	{

	//	if(a == 0 && b == 0)

	//	break;

		memset(xx,'#',sizeof(xx));

		getchar();

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

		{

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

			{

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

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

				{

					x1 = i;

					y1 = j;

				}

				else if(xx[i][j] != 'X')

				{

					bb[xx[i][j] - '0'][0] = i;

					bb[xx[i][j] - '0'][1] = j;

				}

			}

			getchar();

		}

		bb[0][0] = x1;

		bb[0][1] = y1;

		sum = 0;

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

		{

			vv.x = bb[i-1][0];

			vv.y = bb[i-1][1];

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

			vis[vv.x][vv.y] = 0;

			qq.push(vv);

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

		}

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

	}

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.2084055012321913x):
#include <stdio.h>  

#include <string.h>  

#include <queue>  

#define MAX_W 1000  

#define MAX_H 1000  

#define MAX_N 9  

  

using namespace std;  

  

char m[MAX_H][MAX_W + 1];  

int w, h, n;  

int gx[MAX_N + 1], gy[MAX_N + 1];  

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

  

int bfs(int sx, int sy, int gx, int gy)  

{  

    int d[MAX_H][MAX_W];  

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

    queue<int> que;  

    que.push(sx * w + sy);  

    d[sx][sy] = 0;  

          

    while(que.size())  

    {  

        int x = que.front()/w, y = que.front()%w;  

        que.pop();  

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

            break;  

  

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

            int nx = x + dx[di], ny = y + dy[di];  

            if(nx >= 0 && nx < h && ny >= 0 && ny < w && 'X' != m[nx][ny] && -1 == d[nx][ny]){  

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

                que.push(nx * w + ny);  

            }  

        }  

    }  

    return d[gx][gy];  

}  

  

void solve()  

{  

    int ans = 0;  

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

        ans += bfs(gx[i], gy[i], gx[i + 1], gy[i + 1]);  

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

}  

  

int main()  

{  

    scanf("%d%d%d", &h, &w, &n);  

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

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

          

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

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

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

                gx[m[i][j] - '0'] = i, gy[m[i][j] - '0'] = j;  

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

                gx[0] = i, gy[0] = j;  

        }  

  

    if(w || h)  

        solve();  

    return 0;  

}