// 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: 2.6544681953994025x):
#include <cstdio>

#include <cstring>

#include <algorithm>

#include <cmath>

#include <climits>

#include <queue>

using namespace std;

const int N=1000;

char maze[N][N];

int h,w,n;

int sx,sy,gx,gy;

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

int d[N][N];

const int INF=INT_MAX;

int ans;

struct node

{

    node(int xx=0,int yy=0,int tt=0,char ss=0):x(xx),y(yy),t(tt),s(ss){}

    int x;

    int y;

    int t;

    char s;

};

bool read()

{

    memset(maze,0,sizeof(maze));

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

    getchar();

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

    {

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

        {

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

            if(maze[i][j]=='S') sx=j,sy=i;

            if(maze[i][j]=='0'+n) gy=i,gx=j;

        }

        getchar();

    }

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

       for(int j=0;j<w;j++) d[i][j]=INF;

    return 1;

}

void show()

{

    //printf("h:%d w:%d\n",h,w);

    //printf("maze[%d][%d]=%d\n",0,2,maze[0][2]);

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

    {

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

        {

            if(d[i][j]!=INF) printf("%d ",d[i][j]);

            else printf("- ");

        }

        printf("\n");

    }

    //printf("sy:%d sx:%d\n",sy,sx);

}

void init(int h,int w)

{

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

        for(int j=0;j<w;j++) d[i][j]=INF;

}

int bfs()

{

   queue<node> que;

   que.push(node(sx,sy,0,'1'));

   d[sy][sx]=0;

   while(!que.empty())

   {



       node t=que.front();que.pop();

       //printf("%c\n",t.s);

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

       {

           int nx=t.x+dir[i][0];

           int ny=t.y+dir[i][1];

           if(0<=nx&&nx<w&&0<=ny&&ny<h&&d[ny][nx]==INF&&maze[ny][nx]!='X'/*(maze[ny][nx]=='.'||maze[ny][nx]==t.s)*/)

           {

               if(maze[ny][nx]=='0'+n&&maze[ny][nx]==t.s)

               {

                   //printf("%c in return",maze[ny][nx]);

                   return ans+=d[t.y][t.x]+1;

               }

               if(maze[ny][nx]==t.s)

               {

                   //printf("%c d\n",maze[ny][nx]);

                   maze[ny][nx]='.';

                    d[ny][nx]=d[t.y][t.x]+1;

                    ans+=d[ny][nx];

                    //show();

                    while(!que.empty()) que.pop();

                    init(h,w);

                    d[ny][nx]=0;

                   que.push(node(nx,ny,0,t.s+1));

                   break;

               }

               else

               {

                   que.push(node(nx,ny,0,t.s));

                    d[ny][nx]=d[t.y][t.x]+1;

               }

           }

       }

       //int size=que.size();

        //printf("size:%d\n",size);

   }

   return 1/*d[gy][gx]*/;

}

int main()

{

    while(~scanf("%d%d%d",&h,&w,&n))

    {

        getchar();

        memset(maze,0,sizeof(maze));

        ans=0;

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

        {

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

            {

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

                if(maze[i][j]=='S') sx=j,sy=i;

                if(maze[i][j]=='0'+n) gy=i,gx=j;

            }

            getchar();

        }

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

            for(int j=0;j<w;j++) d[i][j]=INF;

        bfs();

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

    }

    return 0;

}