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

#include<string.h>

#include<algorithm>

#include<queue>



using namespace std;



struct node

{

    int s;

    int x,y;

};



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

int vis[1010][1010];

int n,m,k,sx[20],sy[20];

char mp[1010][1010];



int bfs(int x,int y,int ex,int ey)

{

    queue<node> q;

    node a,b,d;

    a.x = x;

    a.y = y;

    a.s = 0;

    vis[x][y] = 1;

    q.push(a);

    while(!q.empty())

    {

        b = q.front();

        q.pop();

        if(b.x == ex && b.y == ey)

        {

            return b.s;

        }

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

        {

            d.x = b.x + dir[i][0];

            d.y = b.y + dir[i][1];

            if(d.x >= 0 && d.x < n && d.y >= 0 && d.y < m && vis[d.x][d.y] == 0)

            {

                if(mp[d.x][d.y] >= '1' && mp[d.x][d.y] <= '9' || mp[d.x][d.y] == '.')

                {

                    vis[d.x][d.y] = 1;

                    d.s = b.s + 1;

                    q.push(d);

                }

            }

        }

    }

}



int main()

{

    while(~scanf("%d%d%d",&n,&m,&k))

    {

        int i,j,t;



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

        {

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

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

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

                {

                    sx[0] = i;

                    sy[0] = j;

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

                }

        }

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

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

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

                {

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

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

                }

        int ans = 0;

        for(i = 1; i <= k; i++)

        {

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

            ans += bfs(sx[i-1],sy[i-1],sx[i],sy[i]);

        }

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

    }

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.038066724641302x):
    #include <iostream>

    #include <queue>

    using namespace std;

    int w, h, n;

    char map[1024][1024];

    // 各点到当前工厂的距?

    int d[1024][1024];

    const int direction[4][2] = {

    	{ -1, 0 },

    	{ 1, 0 },

    	{ 0, -1 },

    	{ 0, 1 },

    };

     

    int factory[16][2];

    typedef pair<int, int> P;

     

     

     

    //************************************

    // Method:    bfs

    // FullName:  bfs

    // Access:    public 

    // Returns:   int

    // Qualifier:

    // Parameter: const int & sx 起点x

    // Parameter: const int & sy 起点y

    // Parameter: const int & gx ?点x

    // Parameter: const int & gy ?点y

    //************************************

    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 + direction[i][0];

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

    			// 是否可以移?，并且?点没有???

    			if (0 <= nx && nx < w && 0 <= ny && ny < h && map[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];

    }

     

    ///////////////////////////SubMain//////////////////////////////////

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

    {

     

    	cin >> h >> w >> n;

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

    	{

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

    		{

    			cin >> map[j][i];

    		}

    	}

     

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

    	{

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

    		{

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

    			{

    				factory[0][0] = j;

    				factory[0][1] = i;

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

    			}

    			else if (isdigit(map[j][i]))

    			{

    				int index = map[j][i] - '0';

    				factory[index][0] = j;

    				factory[index][1] = i;

    			}

    		}

    	}

     

    	int step = 0;

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

    	{

    		// 按?序吃遍中?

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

    	}

    	

    	cout << step << endl;

     

    	return 0;

    }

    ///////////////////////////End Sub//////////////////////////////////