// Slower C++ solution:
//

//  AOJ 0558 Chees

//

//  Created by TaoSama on 2015-02-20

//  Copyright (c) 2014 TaoSama. All rights reserved.

//

#include <algorithm>

#include <cctype>

#include <cmath>

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <iomanip>

#include <iostream>

#include <map>

#include <queue>

#include <string>

#include <set>

#include <vector>

#define CLR(x,y) memset(x, y, sizeof(x))



using namespace std;

const int INF = 0x3f3f3f3f;

const int MOD = 1e9 + 7;

const int N = 1e5 + 10;



struct Point {

	int x, y;

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

} c[15];

int n, m, k, dp[1005][1005];

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

char a[1005][1005];



int bfs(int x) {

	memset(dp, 0x3f, sizeof dp);

	queue <Point> q; q.push(c[x - 1]);

	dp[c[x - 1].x][c[x - 1].y] = 0;

	while(!q.empty()) {

		Point cur = q.front(); q.pop();

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

			Point nxt(cur.x + d[i][0], cur.y + d[i][1]);

			if(nxt.x < 1 || nxt.x > n || nxt.y < 1 || nxt.y > m

			        || a[nxt.x][nxt.y] == 'X') continue;

			if(dp[nxt.x][nxt.y] == INF) {

				dp[nxt.x][nxt.y] = dp[cur.x][cur.y] + 1;

				q.push(nxt);

			}

		}

	}

	return dp[c[x].x][c[x].y];

}

int main() {

#ifdef LOCAL

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

//	freopen("out.txt","w",stdout);

#endif

	ios_base::sync_with_stdio(0);



	while(cin >> n >> m >> k) {

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

			for(int j = 1; j <= m; ++j) {

				cin >> a[i][j];

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

					c[0].x = i, c[0].y = j;

				if(isdigit(a[i][j]))

					c[a[i][j] - '0'].x = i, c[a[i][j] - '0'].y = j;

			}

		}

		int ans = 0;

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

			ans += bfs(i);

		cout << ans << endl;

	}

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.095325608694655x):
#include <iostream>

#include <queue>

using namespace std;

int w, h, n;

char map[1024][1024];

int d[1024][1024];

const int direction[4][2] = {

    { -1, 0 },

    { 1, 0 },

    { 0, -1 },

    { 0, 1 },

};

int factory[16][2];

typedef pair<int, int> P;

int bfs(int sx, int sy, int gx, int gy)

{

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

    {

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

        {

            d[i][j] = -1;

        }

    }

    queue<P> que;

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

    d[sx][sy] = 0;

    while (que.size())

    {

        const 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 + direction[i][0];

            int ny = p.second + direction[i][1];

            if (0 <= nx && nx < h && 0 <= ny && ny < w && map[nx][ny] != 'X' && d[nx][ny] == -1)

            {

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

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

            }

        }

    }



    return d[gx][gy];

}



int main(int argc, char *argv[])

{



    cin >> h >> w >> n;

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

    {

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

        {

            cin >> map[i][j];

        }

    }



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

    {

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

        {

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

            {

                factory[0][0] = i;

                factory[0][1] = j;

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

            }

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

            {

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

                factory[index][0] = i;

                factory[index][1] = j;

            }

        }

    }



    int step = 0;

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

    {

        step += bfs(factory[i][0], factory[i][1], factory[i + 1][0], factory[i + 1][1]);

    }



    cout << step << endl;



    return 0;

}

///////////////////////////End Sub//////////////////////////////////