// Slower C++ solution:
//

// Create by 神舟 on 2015-02-21

//



#include <iostream>

#include <cstdio>

#include <cstring>

#include <cmath>

#include <cstdlib>

#include <algorithm>

#include <cctype>

#include <stack>

#include <queue>

#include <map>

#include <string>

#include <set>

#include <vector>

using namespace std;



#define CLR(x) memset(x,0,sizeof x)

#define ll long long

#define inf 0x3f3f3f3f

const int maxn=1e3+5;

const int MOD=5e5+5;

int n,m,t,sx,sy,ex,ey;

char word[maxn][maxn];

int path[maxn][maxn];

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



struct pnt

{

    int x,y;

    pnt(int x=0,int y=0):x(x),y(y){};

};



void bfs()

{

    memset(path,0x3f,sizeof path);

    queue <pnt> que;

    pnt p,np;

    p.x=sx,p.y=sy;

    path[sx][sy]=0;

    que.push(p);

    while(!que.empty()){

        p=que.front();que.pop();

        if(p.x==ex&&p.y==ey) {return;}

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

            np.x=p.x+dir[i][0];

            np.y=p.y+dir[i][1];

            if(np.x>0 && np.x<=n && np.y>0 && np.y<=m && path[np.x][np.y]>path[p.x][p.y]+1 && word[np.x][np.y]!='X')

            {

                path[np.x][np.y]=path[p.x][p.y]+1;

                que.push(np);

            }

        }

    }

}

int main()

{

#ifdef LOCAL

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

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

#endif

	ios_base::sync_with_stdio(0);



	while(scanf("%d%d%d",&n,&m,&t)!=EOF){

        ans=0;

        CLR(word);

        for(int i=1;i<=n;scanf("%s",word[i++]+1));

        for(int i=1;i<=n;i++) for(int j=1;j<=m;j++) if(word[i][j]=='S') word[i][j]='0';

        for(int k=0;k<t;k++){

            char tp=k+'0';

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

                if(word[i][j]==tp) sx=i,sy=j;

                if(word[i][j]==tp+1) ex=i,ey=j;

            }

            bfs();

            ans+=path[ex][ey];

            //printf("%d\t",path[ex][ey]);

        }

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

	}



	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 3.001003085940569x):
#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;

}