// 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: 2.967564055618797x):
#include <iostream>

#include <stdlib.h>

#include <queue>

#include <cstring>

#define MAX_NUM 1010

using namespace std;

int H, W, N;

bool flag[MAX_NUM][MAX_NUM] = {false};                            //??是否已遍??

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



class Node {

  public:

    Node();

    Node(int x, int y, int step);

    ~Node();

    int x;

    int y;

    int step;

};



Node::Node() {

}



Node::Node(int x, int y, int step) {

    this->x = x;

    this->y = y;

    this->step = step;

}



Node::~Node() {

}



int BFS(char map[][MAX_NUM], int sx, int sy, int ex, int ey) {

    queue<Node> que;                                                  //第一次出?Memory Limit Exceeded,一定不能使用new来?行?建

    Node node(sx, sy, 0);

    que.push(node);

    flag[sx][sy] = true;                                              //将遍?的?点?置?true



    while(!que.empty()) {

        Node cur = que.front();

        que.pop();



        if(cur.x == ex && cur.y == ey) {

            return cur.step;



        } else {

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

                int k = cur.x + dir[i][0];

                int v = cur.y + dir[i][1];



                if(k >= 0 && k < H && v >= 0 && v < W && map[k][v] != 'X' && !flag[k][v]) { //将可到?并且尚未遍?的?点加入?列

                    Node temp(k, v, cur.step + 1);

                    que.push(temp);

                    flag[k][v] = true;

                }

            }

        }

    }



    return -1;

}



int main() {

    int sx, sy, arr[10][2];

    char map[MAX_NUM][MAX_NUM];



    if(cin >> H >> W >> N && H && W) {

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

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

                cin >> map[i][j];



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

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

                    sx = i;

                    sy = j;

                }



                if(isdigit(map[i][j])) {

                    int index = map[i][j] - '0';

                    arr[index][0] = i;

                    arr[index][1] = j;

                }

            }

        }



        arr[0][0] = sx;

        arr[0][1] = sy;

        int res = 0;



        for(int i = 0; i + 1 <= N; i++) {

            memset(flag, false, sizeof(flag));

            res += BFS(map, arr[i][0], arr[i][1], arr[i + 1][0], arr[i + 1][1]);

        }



        cout << res << endl;

    }



    return 0;

}