// 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: 5.15453668744462x):
#include<iostream>

#include<queue>

#include<cstdio>

#include<cstring>

#include<utility>

using namespace std;

struct dir

{

	int x,y;

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

char hole[1005][1005];

int d[1005][1005],h,w,factory[10][2];

typedef pair<int,int> P;

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

{

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

	{

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

		{

			d[i][j] = -1;

		}

	}

	//memset(d,-1,sizeof(d));

	queue<P> que;

	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+dir[i].x;

		int ny=p.second+dir[i].y;

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

		{

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

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

		}

		}

	}

	return d[gx][gy];

}

int main()

{

	int sx,sy,i,j,step=0,n;

	scanf("%d%d%d\n",&h,&w,&n);

	//cin>>h>>w>>n;

	for(i=0;i<h;i++,getchar())

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

		{

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

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

			{

				factory[0][0]=i;

				factory[0][1]=j;

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

			}

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

			{

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

			factory[index][0]=i;

			factory[index][1]=j;

			}

		}

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

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

	//cout<<step<<endl;

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

	return 0;

 }