// Slower C++ solution:
#include<stdio.h>

#include<string.h>

#include<algorithm>

#include<queue>



using namespace std;



struct node

{

    int s;

    int x,y;

};



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

int vis[1010][1010];

int n,m,k,sx[20],sy[20];

char mp[1010][1010];



int bfs(int x,int y,int ex,int ey)

{

    queue<node> q;

    node a,b,d;

    a.x = x;

    a.y = y;

    a.s = 0;

    vis[x][y] = 1;

    q.push(a);

    while(!q.empty())

    {

        b = q.front();

        q.pop();

        if(b.x == ex && b.y == ey)

        {

            return b.s;

        }

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

        {

            d.x = b.x + dir[i][0];

            d.y = b.y + dir[i][1];

            if(d.x >= 0 && d.x < n && d.y >= 0 && d.y < m && vis[d.x][d.y] == 0)

            {

                if(mp[d.x][d.y] >= '1' && mp[d.x][d.y] <= '9' || mp[d.x][d.y] == '.')

                {

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

                    d.s = b.s + 1;

                    q.push(d);

                }

            }

        }

    }

}



int main()

{

    while(~scanf("%d%d%d",&n,&m,&k))

    {

        int i,j,t;



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

        {

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

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

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

                {

                    sx[0] = i;

                    sy[0] = j;

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

                }

        }

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

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

                if(mp[i][j] >= '1' && mp[i][j] <= '9')

                {

                    sx[mp[i][j]-'0'] = i;

                    sy[mp[i][j]-'0'] = j;

                }

        int ans = 0;

        for(i = 1; i <= k; i++)

        {

            memset(vis,0,sizeof(vis));

            ans += bfs(sx[i-1],sy[i-1],sx[i],sy[i]);

        }

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

    }

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 2.6237124599286825x):
/*Lucky_Glass*/

#include<cstdio>

#include<cstring>

#include<algorithm>

#include<queue>

using namespace std;

const int MAXN=1000;

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

struct QUEUE{

	int x,y,dep;

	QUEUE(){}

	QUEUE(int _x,int _y,int _dep){x=_x;y=_y;dep=_dep;}

};

int r,c,n;

int goal[10][2];

bool vis[MAXN+5][MAXN+5];

char maz[MAXN+5][MAXN+5];

int BFS(int *beg,int cnt){

	memset(vis,false,sizeof vis);

	queue<QUEUE> que;

	que.push(QUEUE(beg[0],beg[1],0));

	while(!que.empty())

	{

		QUEUE pre=que.front();que.pop();

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

		{

			int X=pre.x+dir[i][0],Y=pre.y+dir[i][1],depth=pre.dep+1;

			if(X<1 || X>r || Y<1 || Y>c || maz[X][Y]=='X' || vis[X][Y]) continue;

			vis[X][Y]=true;

			if(X==goal[cnt][0] && Y==goal[cnt][1])

				return depth;

			que.push(QUEUE(X,Y,depth));

		}

	}

	return -1;

}

int main(){

	scanf("%d%d%d",&r,&c,&n);

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

	{

		scanf("%s",maz[i]+1);

		for(int j=1;j<=c;j++)

		{

			if('1'<=maz[i][j] && maz[i][j]<='9')

				goal[maz[i][j]-'0'][0]=i,

				goal[maz[i][j]-'0'][1]=j,

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

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

				goal[0][0]=i,

				goal[0][1]=j,

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

		}

	}

	int ans=0;

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

		ans+=BFS(goal[i-1],i);

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

	return 0;

}//