// Slower C++ solution:
//??-2015-11-1

# include <cstdio>

# include <string>

# include <cstring>

# include <algorithm>

# include <iostream>

# include <queue>



using namespace std;



int direction[4][2] = { { -1, 0 }, { 1, 0 }, { 0, -1 }, {0,1} };                  //四个方向，上下左右

struct node

{

	int w, h;

	int step;

};

struct node2

{

	int h, w, value;

};

int H, W, N;

string s[1005];

int vis[1005][1005];

int cmp(node2 a, node2 b)

{

	if (a.value < b.value)

		return 1;

	else

		return 0;

}

int DFS(int begin_h, int begin_w, int end_h, int end_w)

{

	int i, j,w = 0;

	queue<node>Q;

	node temp;

	temp.h = begin_h;

	temp.w = begin_w;

	temp.step = 0;

	Q.push(temp);

	vis[begin_h][begin_w] = 1;

	while (!Q.empty())                     //?列不空的?

	{

		node temp1 = Q.front();

		Q.pop();

		//printf("%d\n", w++);

		if (temp1.h == end_h&&temp1.w == end_w)

		{

			return temp1.step;

		}

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

		{

			if (temp1.h + direction[i][0] >= 0 && temp1.h + direction[i][0] < H&&temp1.w + direction[i][1] >= 0 && temp1.w + direction[i][1] < W&&!vis[temp1.h + direction[i][0]][temp1.w + direction[i][1]] && s[temp1.h + direction[i][0]][temp1.w + direction[i][1]] == '.')

			{

				node temp2;

				temp2.h = temp1.h + direction[i][0];

				temp2.w = temp1.w + direction[i][1];

				temp2.step = temp1.step + 1;

				vis[temp1.h + direction[i][0]][temp1.w + direction[i][1]] = 1;

				Q.push(temp2);

			}

		}

	}

}

int main(void)

{

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

	int i, j,k = 1;

	int all_step = 0;

	int s_h, s_w,e_h,e_w;

	//freopen("in.txt", "r", stdin);

	scanf("%d%d%d", &H, &W, &N);

	node2 node1[20];

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

	{

		cin >> s[i];

		for (j = 0; j < s[i].length(); j++)

		{

			if (s[i][j] >= '0'&&s[i][j] <= '9')

			{

				node1[k].h = i;

				node1[k].w = j;

				node1[k].value = s[i][j] - '0';                //保留?

				k++;

				s[i][j] = '.';                                  //?了BFS的?候?理一致

			}

			else if (s[i][j] == 'S')                            //?始?点

			{

				s_h = i;

				s_w = j;

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

			}

		}

	}

		sort(node1+1, node1 + N+1, cmp);                             //先排好序

		node1[0].h = s_h;                                            //?了使下面循?一?

		node1[0].w = s_w;

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

		{

			e_h = node1[i+1].h;                                      //?点的坐?

			e_w = node1[i+1].w;

			s_h = node1[i].h;

			s_w = node1[i].w;

			//printf("step=%d\n", DFS(s_h, s_w, e_h, e_w));

			all_step += DFS(s_h, s_w, e_h, e_w);                       //原来的?点??起始点

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

		}

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

	

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.8378873744829058x):
#include <iostream>

#include <stdio.h>

#include <cstring>

#include <queue>

using namespace std;



char ma[1005][1005];int vis[1005][1005];

int w,h,n;



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

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



struct node

{

    int x,y,time;

};

node start;



void bfs(char ed)

{

    queue<node> que;

    que.push(start);

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

    while(!que.empty())

    {

        node no=que.front();

        que.pop();

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

        {

            int x=no.x+dx[i];

            int y=no.y+dy[i];

            if(vis[x][y]||x>=h||x<0||y>=w||y<0||ma[x][y]=='X')

                continue;

            if(ma[x][y]==ed)

            {

                start.x=x;

                start.y=y;

                start.time=no.time+1;

                return ;

            }

            vis[x][y]=1;

            node no1;

            no1.x=x;no1.y=y;no1.time=no.time+1;

            que.push(no1);

        }

    }

}



int main()

{

    while(~scanf("%d %d %d", & h, & w, & n))

    {

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

        {

            scanf("%s",&ma[i]);

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

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

                {

                    start.x=i;

                    start.y=j;

                    start.time=0;

                }



        }

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

            {

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

                bfs(i+'1');

            }



            printf("%d\n",start.time);

    }

    return 0; 

}