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

#include<cstring>

#include<queue>

#define maxn 1002

#define maxc 10

using namespace std;

struct point{

    int r,c;

};

char graph[maxn][maxn];

int len[maxn][maxn];

bool mark[maxn][maxn];

point node[maxc];

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

int main(void){

    int h,w,cheese,tr,tc,answer=0;

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

    memset(graph,0,sizeof(graph));

    memset(node,0,sizeof(node));

    for(int i=1;i<=h;i++) for(int j=1;j<=w;j++){

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

        while(graph[i][j]==' ' || graph[i][j]=='\n');

        if(graph[i][j]>='0' && graph[i][j]<='9'){

            node[graph[i][j]-'0'].r=i;

            node[graph[i][j]-'0'].c=j;

        }

        else if(graph[i][j]=='S'){

            node[0].r=i;

            node[0].c=j;

        }

    }

    for(int cnt=0;cnt<cheese;cnt++){

        memset(len,0,sizeof(len));

        memset(mark,false,sizeof(mark));

        for(int i=0;i<=h+1;i++){mark[i][0]=true;mark[i][w+1]=true;}

        for(int j=0;j<=w+1;j++){mark[0][j]=true;mark[h+1][j]=true;}

        queue<point> q;

        q.push(node[cnt]);

        len[node[cnt].r][node[cnt].c]=0;

        point ongo,togo;

        while(!q.empty()){

            ongo=q.front();

            q.pop();

            if(mark[ongo.r][ongo.c]) continue;

            mark[ongo.r][ongo.c]=true;

            if(ongo.r==node[cnt+1].r && ongo.c==node[cnt+1].c){

                answer+=len[ongo.r][ongo.c];

                break;

            }

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

                togo.r=ongo.r+dir[i][0];togo.c=ongo.c+dir[i][1];

                if(mark[togo.r][togo.c]==false && graph[togo.r][togo.c]!='X'){

                    len[togo.r][togo.c]=len[ongo.r][ongo.c]+1;

                    q.push(togo);

                }

            }

        }

    }

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

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 3.685491638664069x):
/*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;

}//