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

#include<cstdio>

#include<queue>

#include<utility>

#include<cstring>

using namespace std;

char map[1005][1005];

bool vis[1005][1005];

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

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

int sx,sy;

int h,w;

int bfs(int n){

	memset(vis,false,sizeof(vis));

	queue<pair<pair<int,int>,int> >que;

	que.push(make_pair(make_pair(sx,sy),0));

	while(!que.empty()){

		pair<int,int>now=que.front().first;

		int cnt=que.front().second;

		que.pop();

		if(map[now.first][now.second]==n+48){

			sx=now.first;

			sy=now.second;

			return cnt;

		}

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

			int _x=now.first+dx[i];

			int _y=now.second+dy[i];

			if(_x<0||_y<0||_x>=h||_y>=w||map[_x][_y]=='X'||vis[_x][_y]){

				continue;

			}

			vis[_x][_y]=true;

			que.push(make_pair(make_pair(_x,_y),cnt+1));

		}

	}

}

int main(){

	int n;

	while(cin>>h>>w>>n){

		memset(map,0,sizeof(map));

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

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

		}

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

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

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

					sx=i;

					sy=j;

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

					break;

				}

			}

		}

		int count=0;

		for(int k=1;k<=n;k++){

			count+=bfs(k);

		}

		cout<<count<<endl;

	}

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.5067314081918288x):
#include <iostream>

#include <cctype>

#include <queue>

#include <string.h>

using namespace std;

const int DIRECTSIZE = 4;

struct _direct {

    int drow;

    int dcol;

} direct[DIRECTSIZE] = {{0, -1}, {0, 1}, {-1, 0}, {1, 0}};



const int N = 1000;

const int N2 = 10;

char grid[N][N], visited[N][N];

int h, w, n;

struct _factory {

    int row, col;

} factory[N2];



struct _node {

    int row, col, level;

};



int bfs(int n, char goal)

{

    memset(visited, 0, sizeof(visited));



    _node start={factory[n-1].row, factory[n-1].col, 0}, temp;



    visited[start.row][start.col] = 1;



    queue<_node> q;

    q.push(start);



    while(!q.empty()) {

        _node front = q.front();

        q.pop();



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

            int nextrow = front.row + direct[i].drow;

            int nextcol = front.col + direct[i].dcol;

            if( 0 <= nextrow && nextrow < h && 0 <= nextcol && nextcol < w) {

                if(grid[nextrow][nextcol] == goal) {

                    return front.level + 1;

                } else if(visited[nextrow][nextcol] == 0 && grid[nextrow][nextcol] != 'X') {

                    visited[nextrow][nextcol] = 1;

                    temp.row = nextrow;

                    temp.col = nextcol;

                    temp.level = front.level + 1;

                    q.push(temp);

                }

            }

        }

    }



    return 0;

}



int main()

{

    while(cin >> h >> w >> n) {

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

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

                cin >> grid[i][j];



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

                    factory[0].row = i;

                    factory[0].col = j;

                } else if(isdigit(grid[i][j])) {

                    factory[grid[i][j] - '0'].row = i;

                    factory[grid[i][j] - '0'].col = j;

                }

            }



        int minstep = 0;

        char goal = '1';

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

            minstep += bfs(i, goal);

            goal++;

        }



        cout << minstep << endl;

    }



    return 0;

}