// Slower C++ solution:
/************************************************

* Author        :somniloquy

* Created Time  :2015/10/30 16:15:09

 ************************************************/



#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;

}

// Faster C++ solution for the same problem (measured speedup: 4.928429499744682x):
#include<iostream>

#include<cstdio>

#include<vector>

#include<cmath>

#include<map>

#include<set>

#include<queue>

#include<cstring>

#include<algorithm>

using namespace std;

const int maxn = 1000 + 8;

#define inf 0x3f3f3f3f



struct node

{

    int x,y;

    node(int x = 0,int y = 0):x(x),y(y){}

}s,current,st,nd;



int h,w,n;

int step[maxn][maxn];

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

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

string Map[maxn];

int sum = 0;



int bfs()

{

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

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

            step[i][j] = inf;

        }

    }

    queue<node> q;

    step[st.x][st.y] = 0;

    q.push(st);

    while(!q.empty())

    {

        current = q.front();

        q.pop();

        if(current.x == nd.x && current.y == nd.y) break;

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

        {

            s.x = current.x + dx[i];

            s.y = current.y + dy[i];

            if(s.x >= 0 && s.x < h && s.y >= 0 && s.y < w && Map[s.x][s.y] != 'X' && step[s.x][s.y] == inf)

            {

                step[s.x][s.y] = step[current.x][current.y] + 1;

                q.push(s);

            }

        }

    }

    return step[nd.x][nd.y];

}

int main()

{

    while(cin >> h >> w >> n)

    {

        sum = 0;

        for(int i = 0 ; i < h; ++i) cin >> Map[i];

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

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

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

                    st.x = i;

                    st.y = j;

                }

            }

        }



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

        {

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

            {

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

                {

                    if(Map[j][k] == '1' + i)

                    {

                        nd.x = j; nd.y = k;

                        sum += bfs();

                        st.x = j; st.y = k;

                    }

                }

            }

        }

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

    }

    return 0;

}



/*

3 3 1

S..

...

..1

4 5 2

.X..1

....X

.XX.S

.2.X.

10 10 9

.X...X.S.X

6..5X..X1X

...XXXX..X

X..9X...X.

8.X2X..X3X

...XX.X4..

XX....7X..

X..X..XX..

X...X.XX..

..X.......

*/