// Slower C++ solution:
#include <iostream>

#include <cmath>

#include <queue>

#include <cstdio>

#include <cstring>

#include <algorithm>



#define INF 0x7f7f7f7f

#define PI acos(-1.0)



#define L(x)    (x) << 1

#define R(x)    (x) << 1 | 1

#define lowbit(x)   (x)&(-x)

#define Mid(l, r)   (l + r) >> 1

#define Min(x, y)   (x) < (y) ? (x) : (y)

#define Max(x, y)   (x) < (y) ? (y) : (x)

#define iabs(x)     (x) < 0 ? -(x) : (x)

#define CLR(arr, val)    memset(arr, val, sizeof(arr))



using namespace std;



char map[1024][1024];

bool vis[1024][1024];

int cur, h, w;

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



struct node {

	int x, y, step;

} sta, now;



bool check(int x, int y) {

	if (x >= 0 && x < h && y >= 0 && y < w && !vis[x][y] && map[x][y] != 'X')	return true;

	return false;

}







void bfs(node s) {

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



	queue<node> que;

	s.step = 0;

	que.push(s);

	node next;

	while (!que.empty()) {

//		cout << "h\n";

		s = que.front();

//		cout << s.x << ' ' << s.y << ' ' << cur << endl;

		que.pop();

		if (map[s.x][s.y] == cur + '0')	{

			sta = s;

			return ;

//			s.step;

		}



//		cout << "a\n";

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

//			cout << i << endl;

			next.x = s.x + dir[i][0];

			next.y = s.y + dir[i][1];

			next.step = s.step + 1;

			if (check(next.x, next.y)) {

				vis[next.x][next.y] = true;

				que.push(next);

			}



		}

	}

}



int main() {

	int n;

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

//		memset(map, 0, sizeof(map));

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

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

				cin >> map[i][j];

				if (map[i][j] == 'S')	sta.x = i, sta.y = j, map[i][j] = '.';

			}

		}

		sta.step = 0;

		int ans = 0;

		for (cur = 1; cur <= n; cur++) {

			bfs(sta);

			ans += sta.step;

			//cout << ans << endl;

		}

		cout << ans << endl;

	}

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 2.0457287703436604x):
#include<iostream>

#include<algorithm>

#include<queue>

const int INF = 100000000;

using namespace std;

typedef pair<int, int> P;

char a[1005][1005];

int N, M;

int sx, sy;

int gx, gy;

int d[1005][1005];

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

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

int bfs()

{

	queue<P> que;

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

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

			d[i][j] = INF;

	que.push(P(sx, sy));

	d[sx][sy] = 0;

	while (que.size())

	{

		P p = que.front();

		que.pop();

		if (p.first == gx&&p.second == gy)

			break;

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

		{

			int nx = p.first + dx[i];

			int ny = p.second + dy[i];

			if (nx >= 0 && nx < N&&ny >= 0 && ny < M&&a[nx][ny] != 'X'&&d[nx][ny] == INF)

			{

				que.push(P(nx, ny));

				d[nx][ny] = d[p.first][p.second] + 1;

			}

		}



	}

	return d[gx][gy];

}

int main(void)

{

	while (cin >> N >> M)

	{

		int n, sum = 0;

		cin >> n;

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

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

				cin >> a[i][j];

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

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

				if (a[j][k] == 'S')

				{

					sx = j;

					sy = k;

				}

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

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

				if (a[j][k] == '1')

				{

					gx = j;

					gy = k;

				}

		sum += bfs();

		for (int i = 0; i < n - 1; i++)

		{

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

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

				{

					if (a[j][k] == (char)(i+49))

					{

						sx = j;

						sy = k;

					}

					if (a[j][k] == (char)(i+50))

					{

						gx = j;

						gy = k;

					}

				}

			sum += bfs();



		}

		cout << sum << endl;

	}

}