// Slower C++ solution:
#include "cstring"

#include "cstdio"

#include "queue"

using namespace std;



const int maxn=1024;



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

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



char mp[maxn][maxn];

int vis[maxn][maxn];

int wx[10],wy[10];

int n,m,k;



int bfs(int x1,int y1,int x2,int y2)

{

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

	queue<int>qx;qx.push(x1);

	queue<int>qy;qy.push(y1);

	queue<int>qt;qt.push(0);

	vis[x1][y1]=1;

	

	while(!qx.empty())

	{

		int nx=qx.front();qx.pop();

		int ny=qy.front();qy.pop();

		int nt=qt.front();qt.pop();

		

		if(nx==x2 && ny==y2)return nt;

		

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

		{

			int px=nx+dx[i];

			int py=ny+dy[i];

			if(px>=0 && py>=0 && px<n && py<m && mp[px][py]!='X' && !vis[px][py])

			{

				qx.push(px);

				qy.push(py);

				qt.push(nt+1);

				vis[px][py]=1;

			}

		}

		

	}

	

	return 0;

}



int main()

{

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

	scanf("%d%d%d",&n,&m,&k);

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

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

		{

			mp[i][j]=getchar();

			while(mp[i][j]=='\n' || mp[i][j]=='\0')mp[i][j]=getchar();

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

			{

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

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

			}

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

			{

				wx[0]=i;

				wy[0]=j;

			}	

		}

	int ans=0;

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

		ans+=bfs(wx[i],wy[i],wx[i+1],wy[i+1]);

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

	return 0;

} 


// Faster C++ solution for the same problem (measured speedup: 5.166409924785179x):
#include <iostream>

#include <queue>

using namespace std;

const int INF = 100000000;

typedef pair<int,int> Point;

Point AllPoint[1000];

int W,H;

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

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

char map[1000][1000];

int deep[1000][1000];

int N;

void BFS(Point Start,Point Over){

    queue<Point> que;

    int FirstDeep = deep[Start.first][Start.second];

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

        for (int j = 0;j<W;j++){

            deep[i][j] = INF;

        }

    }

    que.push(Start);

    deep[Start.first][Start.second] = FirstDeep;

    while (que.size()){

        Point p = que.front();

        que.pop();

        if (p.first== Over.first&&p.second == Over.second)

            break;

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

            int ix = p.first+x[i];

            int iy = p.second+y[i];

            if (ix>=0&&ix<=H

                &&iy>=0&&iy<=W

                &&deep[ix][iy] == INF

                &&map[ix][iy]!='X'){

                que.push(Point(ix,iy));

                deep[ix][iy] = deep[p.first][p.second]+1;

            }

        }

    }

}







int main(){

    cin >> H >> W;

    cin >> N;

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

        for (int j = 0;j<W;j++){

            cin >> map[i][j];

            if ((int)map[i][j]-48>=1&&(int)map[i][j]-48<=N){

                AllPoint[(int)map[i][j]-48].first = i;

                AllPoint[(int)map[i][j]-48].second = j;



            }

            if (map[i][j] == 'S'){

                AllPoint[0].first = i;

                AllPoint[0].second = j;

            }

        }

    }

    deep[AllPoint[0].first][AllPoint[0].second] = 0;

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

        BFS(AllPoint[i],AllPoint[i+1]);

    }

    cout << deep[AllPoint[N].first][AllPoint[N].second]<<endl;



    return 0;

}

//#....

//S.##.

//###G.

//#####

//#####



//#S######.#

//......#..#

//.#.##.##.#

//.#........

//##.##.####

//....#....#

//.#######.#

//....#.....

//.####.###.

//....#...G#