// Slower C++ solution:
//

// Create by 神舟 on 2015-02-21

//



#include <iostream>

#include <cstdio>

#include <cstring>

#include <cmath>

#include <cstdlib>

#include <algorithm>

#include <cctype>

#include <stack>

#include <queue>

#include <map>

#include <string>

#include <set>

#include <vector>

using namespace std;



#define CLR(x) memset(x,0,sizeof x)

#define ll long long

#define inf 0x3f3f3f3f

const int maxn=1e3+5;

const int MOD=5e5+5;

int n,m,t,sx,sy,ex,ey;

char word[maxn][maxn];

int path[maxn][maxn];

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



struct pnt

{

    int x,y;

    pnt(int x=0,int y=0):x(x),y(y){};

};



void bfs()

{

    memset(path,0x3f,sizeof path);

    queue <pnt> que;

    pnt p,np;

    p.x=sx,p.y=sy;

    path[sx][sy]=0;

    que.push(p);

    while(!que.empty()){

        p=que.front();que.pop();

        if(p.x==ex&&p.y==ey) {return;}

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

            np.x=p.x+dir[i][0];

            np.y=p.y+dir[i][1];

            if(np.x>0 && np.x<=n && np.y>0 && np.y<=m && path[np.x][np.y]>path[p.x][p.y]+1 && word[np.x][np.y]!='X')

            {

                path[np.x][np.y]=path[p.x][p.y]+1;

                que.push(np);

            }

        }

    }

}

int main()

{

#ifdef LOCAL

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

	//freopen("out.txt","w",stdout);

#endif

	ios_base::sync_with_stdio(0);



	while(scanf("%d%d%d",&n,&m,&t)!=EOF){

        ans=0;

        CLR(word);

        for(int i=1;i<=n;scanf("%s",word[i++]+1));

        for(int i=1;i<=n;i++) for(int j=1;j<=m;j++) if(word[i][j]=='S') word[i][j]='0';

        for(int k=0;k<t;k++){

            char tp=k+'0';

            for(int i=1;i<=n;i++) for(int j=1;j<=m;j++){

                if(word[i][j]==tp) sx=i,sy=j;

                if(word[i][j]==tp+1) ex=i,ey=j;

            }

            bfs();

            ans+=path[ex][ey];

            //printf("%d\t",path[ex][ey]);

        }

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

	}



	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.2143438045967272x):
#include <iostream>

#include <queue>

#include <string.h>

using namespace std;

typedef pair<int, int> P;

int sx,sy,H,W,N;

char map1[1002][1002];

int step[1002][1002];

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

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

void find1(int g){

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

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

        if(map1[i][k] == 'S' || map1[i][k] == (g+48)){

        if(map1[i][k] == 'S') map1[i][k] ='.';

        sx = i; sy = k;

        return ;

    }

}



int bfs(int n)

{

    memset(step,-1,sizeof(step));

    queue <P> que;

    que.push(P (sx,sy));

    step[sx][sy] = 0;

    while(que.size()){

        int x = que.front().first, y = que.front().second;

        que.pop();

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

            int xn = x + dx[i], yn = y + dy[i];

            if(xn >= 0 && xn < W && yn >= 0 && yn < H && map1[xn][yn] != 'X' && step[xn][yn] == -1)

                {

                    step[xn][yn] = step[x][y] + 1;

                    if(map1[xn][yn] == (n+48))

                        {

                            return step[xn][yn];

                        }

                    que.push(P(xn, yn));

                }

        }

    }

return 0;

}



int main()

{

    cin >> W >> H >> N;

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

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

        cin >> map1[i][k];

    int step = 0;

    find1(0);

    step += bfs(1);

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

    {



        find1(i);

        step += bfs(i+1);

    }

    cout << step << endl;

    return 0;

}