// 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: 2.0459966135496686x):
#include <iostream>

#include <cstdio>

#include <cstring>

#include <cmath>

#include <vector>

#include <queue>

#include <set>

#include <map>

#include <stack>

#include <utility>

#include <algorithm>

#include <sstream>

using namespace std;



struct Node{

	int x,y;

};



const int max_n=1000+10;

int h,w,n,dx[]={0,0,-1,1},dy[]={-1,1,0,0},d[max_n][max_n],ans=0;

Node sN;

char c[max_n][max_n];



int bfs(int m){

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

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

	        d[i][j]=0;

	queue<Node> q;

	q.push(sN);

	d[sN.x][sN.y]=1;

	while(!q.empty()){

		Node p=q.front();

		q.pop();

		

		if(c[p.x][p.y]=='0'+m){

		    sN.x=p.x;

		    sN.y=p.y;

		}

		else{

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

				Node nN;

				nN.x=p.x+dx[i];

				nN.y=p.y+dy[i];

				if(nN.x>=0 && nN.x<h 

	            && nN.y>=0 && nN.y<w 

			   	&& c[nN.x][nN.y]!='X' && !d[nN.x][nN.y]){

					q.push(nN);

					d[nN.x][nN.y]=d[p.x][p.y]+1;

				}

			}

		}

	}

	return d[sN.x][sN.y]-1;

}



int main(){

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

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

        scanf("%s",c[i]);

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

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

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

            	sN.x=i;

            	sN.y=j;

            	break;

            }

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

    cout<<ans<<endl;

    return 0;

}