// Slower C++ solution:
#include<stdio.h>

#include<string.h>

#include<queue>

#include<algorithm>

#define MAX_N 1002

using namespace std;

struct node{int x,y;};

char _map[MAX_N][MAX_N];

int dp[MAX_N][MAX_N];

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

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

int S_x,S_y;

int h,w,cnt;



node make_node(int x,int y){

	node t;

	t.x=x,t.y=y;

	return t;

}

void solve(){

	queue<node> que;

	int step=0;

	

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

		que.push(make_node(S_x,S_y));

		_map[S_x][S_y]='.';

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

		dp[S_x][S_y]=step;

		while(!que.empty()){

			node t=que.front();que.pop();

			if(_map[t.x][t.y]=='0'+i){

				step=dp[t.x][t.y];

				S_x=t.x,S_y=t.y;

				break;

			}

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

				int x=t.x+ox[j];

				int y=t.y+oy[j];

				if(0<=x&&x<h&&0<=y&&y<w&&_map[x][y]!='X'&&dp[x][y]==-1){

					que.push(make_node(x,y));

					dp[x][y]=dp[t.x][t.y]+1;

				}

			}

		}

		while(!que.empty()) que.pop();

	}

	

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

}



int main()

{

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

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

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

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

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

				if(_map[j][k]=='S')

					S_x=j,S_y=k,j=h,k=w;

		solve();

	}

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 4.965969708502754x):
/* AOJ0558 Cheese */



#include <iostream>

#include <queue>

//#include <string.h>



using namespace std;



const int N = 1000;

char grid[N][N];

int w, h, n;



// 各点到当前工厂的距?

int d[N][N];



const int direct[4][2] = {

    { -1, 0 },

    { 1, 0 },

    { 0, -1 },

    { 0, 1 },

};



int factory[10][2];

typedef pair<int, int> P;



int bfs(const int& sx, const int& sy, const int& gx, const int& gy)

{

    //memset(d, -1, sizeof(d));

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

    {

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

        {

            d[j][i] = -1;

        }

    }

    queue<P> que;

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

    d[sx][sy] = 0;

    while (que.size())

    {

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

        // 如果是?点就?束

        if (p.first == gx && p.second == gy)

        {

            break;

        }



        // 四方向漫游

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

        {

            int nx = p.first + direct[i][0];

            int ny = p.second + direct[i][1];

            // 是否可以移?，并且?点没有???

            if (0 <= nx && nx < w && 0 <= ny && ny < h && grid[nx][ny] != 'X' && d[nx][ny] == -1)

            {

                que.push(P(nx, ny));

                d[nx][ny] = d[p.first][p.second] + 1;

            }

        }

    }



    return d[gx][gy];

}



int main()

{



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

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

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

                cin >> grid[j][i];

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

                    factory[0][0] = j;

                    factory[0][1] = i;

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

                }

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

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

                    factory[grid[j][i] - '0'][1] = i;

                }

            }





        int minstep = 0;

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

            minstep += bfs(factory[i][0], factory[i][1], factory[i + 1][0], factory[i + 1][1]);

        }



        cout << minstep << endl;

    }



    return 0;

}