// Slower C++ solution:


#include<iostream>

#include<cstdio>

#include<deque>

#include<algorithm>



using namespace std;



const int maxn=1e3+5;

const int inf=0x3f3f3f3f;



typedef pair<int,int>P;



int h,w,n,sx,sy,book[maxn][maxn],goal[10],Next[4][2]={{0,1},{1,0},{0,-1},{-1,0}};

char s[maxn][maxn];



int judge(int row,int col)

{

    if(row>=0&&row<h&&col>=0&&col<w){

        return 1;

    }

    return 0;

}



int bfs()

{

    int res=0;

    deque<P>q;

    for(int ci=0;ci<n;ci++){

        fill(book[0],book[0]+maxn*maxn,inf);

        q.push_back(P(sx,sy));

        book[sx][sy]=0;

        while(!q.empty()){

            int x=q.front().first;

            int y=q.front().second;

            q.pop_front();

            if((int)s[x][y]==49+ci){

                goal[ci]=book[x][y];

                sx=x;

                sy=y;

                break;

            }

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

                int nx=x+Next[i][0];

                int ny=y+Next[i][1];

                if(judge(nx,ny)&&s[nx][ny]!='X'&&book[nx][ny]==inf){

                    q.push_back(P(nx,ny));

                    book[nx][ny]=book[x][y]+1;

                }

            }

        }

        q.clear();

        res+=goal[ci];

    }

    return res;

}



int main()

{

    cin>>h>>w>>n;

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

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

            cin>>s[i][j];

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

                sx=i;

                sy=j;

            }

        }

    }

    int res=bfs();

    cout<<res<<endl;

    return 0;

}




// Faster C++ solution for the same problem (measured speedup: 5.08308673901574x):
#include <iostream>

#include <queue>

#include <string>

#include <cstdio>

#include <cstring>

#include <utility>

using namespace std;

typedef pair<int, int> P;

char maze[1005][1005];

int d[1005][1005];

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

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

int h, w, n, hard; 

int si, sj;

const int INF = 0x3f3f3f3f;

int tot = 0; 



void BFS(int ai, int aj){

    queue<P> que;

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

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

            d[i][j] = INF;

        }

    }

    que.push(P(ai, aj));

    d[ai][aj] = 0;

    while(!que.empty()){

        P a = que.front();

        que.pop();

        int x = a.first, y = a.second;

        if(maze[x][y]-'0' == hard){

            tot += d[x][y];

            si = x; sj = y;

            break;

        }

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

            int dx = x+dirx[i], dy = y+diry[i];

            if(dx>=0 && dx<h && dy>=0 && dy<w && maze[dx][dy]!='X' && d[dx][dy]==INF){

                d[dx][dy] = d[x][y]+1;

                que.push(P(dx, dy));

            }

        }

    }

}



int main(int argc, char const *argv[]){

    while(scanf("%d%d%d", &h, &w, &n) != EOF){

        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'){

                    si = i; sj = j;

                }

            }

            getchar();

        }

        tot = 0;

        hard = 1;

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

            BFS(si, sj);

            hard++;

        }

        cout << tot << endl;

    }

    return 0;

}