// Slower C++ solution:
#include<queue>

#include<cstdio>

#include<cstring>

#include<iostream>

#include<algorithm>

#define SC(x) scanf("%d",&x);

#define pr(x)  cout << x << endl;

#define mem(arr,v) memset(arr,v,sizeof arr);

#define bug(x) cout << "#x = " << x <<endl;

const int inf = 0x3f3f3f3f;

const int maxn = 1010;

typedef long long ll;

using namespace std;

char Mz[maxn][maxn],c;

bool vis[maxn][maxn];

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

int M,N,C;

int px[10],py[10];

struct node {

	int x,y,step;

};



int bfs(int des,int sx,int sy) {

	mem(vis,0);

	vis[sx][sy] = 1;

	node nod = {sx,sy,0};

	queue<node> q;

	q.push(nod);



	while(!q.empty()) {

		nod =  q.front();

		q.pop();

		

		int x = nod.x, y = nod.y;

		int step =  nod.step;

		

		if(Mz[x][y] == des + '0')

			return step;

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

			int dx = x + dir[i][0];

			int dy = y + dir[i][1];

			if(Mz[dx][dy] == 'X' || Mz[dx][dy] == -1 || vis[dx][dy])	continue;

			nod = {dx,dy,step + 1};

			q.push(nod);

			vis[dx][dy] = 1;

		}

	}

}



int main() {

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

	cin >> N >> M >> C;

	mem(Mz,-1)

	mem(px,0)  mem(py,0)



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

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

			cin >> c;

			Mz[i][j] = c;

			if(c == '.' || c == 'X')	continue;

			if(c == 'S') px[0] = i, py[0] = j;

			else

				px[c - '0'] = i , py[c - '0'] = j;

		}

	int res = 0;

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

		if(px[i] && py[i]) {

//				dfs(i + 1,px[i],py[i],0);

			res += bfs(i + 1,px[i],py[i]);

		}

	}

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

}

// Faster C++ solution for the same problem (measured speedup: 1.5723221138269916x):
#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;

}