// 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: 1.8352225328420282x):
#include <cstdio>

#include <algorithm>

#include <iostream>

#include <cstring>

#include <queue>



using namespace std;



const int hw_max = 1000 + 5;

char graph[hw_max][hw_max];

int sign[hw_max][hw_max];

int h, w, n, ans;

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

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

struct node

{

    int x;

    int y;

    int time;

} start;



void BFS(node op, char ed)

{

    queue <node> process;

    process.push(op);

    sign[op.x][op.y] = 1;

    while(!process.empty())

    {

        node now = process.front();

        process.pop();

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

        {

            node next = now;

            next.x += dx[i];

            next.y += dy[i];

            next.time ++;

            if(next.x >= 0 && next.x < h && next.y >= 0 && next.y < w && graph[next.x][next.y] != 'X' && !sign[next.x][next.y])

            {

                if(graph[next.x][next.y] == ed)

                {

                    ans += next.time;

                    next.time = 0;

                    start = next;

                        return;

                }

                else

                {

                    process.push(next);

                    sign[next.x][next.y] = 1;

                }

            }

        }

    }

}



int main()

{

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

    {

        getchar();

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

        {

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

            {

                   scanf("%c", & graph[i][j]);

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

                   {

                    start.x = i;

                    start.y = j;

                    start.time = 0;

                   }

            }

            getchar();

        }

        ans = 0;

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

        {

            memset(sign, 0, sizeof(sign));

            BFS(start, '0' + i);

        }

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

    }

    return 0;

}