// Slower C++ solution:
#include"stdio.h"

#include"stdlib.h"

#include"string.h"

#include"algorithm"

#include"queue"

using namespace std;

struct mmm

{

	int x,y;

}vv;

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

char xx[1005][1005];

int bb[11][2];

queue <mmm> qq;

int vis[1005][1005];

int bfs(char t)

{

	int sum = 0;

	int pl = 0;

	while(!qq.empty())

	{

		vv = qq.front();

		int x0 = vv.x;

		int y0 = vv.y;

		//printf("%d %d %d\n",x0,y0,vis[x0][y0]);

		qq.pop();

		if(xx[x0][y0] == t && !pl)

		{

			sum = vis[x0][y0];

			pl = 1;

		}

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

		{

			int xt = x0 + dir[i][0];

			int yt = y0 + dir[i][1];

			if(xx[xt][yt] != '#' && xx[xt][yt] != 'X' && vis[xt][yt] == -1)

			{

				vis[xt][yt] = vis[x0][y0] + 1;

				vv.x = xt;

				vv.y = yt;

				qq.push(vv);

			}

		}

	}

	return sum;

}

int main()

{

	int a,b,c,d,x1,y1,sum;

	while(~scanf("%d %d %d",&a,&b,&c))

	{

	//	if(a == 0 && b == 0)

	//	break;

		memset(xx,'#',sizeof(xx));

		getchar();

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

		{

			for(int j = 1;j <= b;j++)

			{

				xx[i][j] = getchar();

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

				{

					x1 = i;

					y1 = j;

				}

				else if(xx[i][j] != 'X')

				{

					bb[xx[i][j] - '0'][0] = i;

					bb[xx[i][j] - '0'][1] = j;

				}

			}

			getchar();

		}

		bb[0][0] = x1;

		bb[0][1] = y1;

		sum = 0;

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

		{

			vv.x = bb[i-1][0];

			vv.y = bb[i-1][1];

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

			vis[vv.x][vv.y] = 0;

			qq.push(vv);

			sum += bfs(i + '0');

		}

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

	}

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 3.03802922224623x):
#include<cstdio>

#include<cstring>

#include<iostream>

#include<queue>

#include<vector>

#include<algorithm>

#include<string>

#include<cmath>

#include<set>

#include<map>

#include<vector>

#include<stack>

#include<utility>

#include<sstream>

using namespace std;

typedef long long ll;

const int inf = 0x3f3f3f3f;

const int maxn = 1005;

int a[1005][1005];

int x[20], y[20];

int ans, w, h, n;

bool leap[1005][1005];

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

struct Node

{

	int x, y, t;

	Node(int x, int y, int t) :x(x), y(y), t(t){}

};

int work(int xx, int yy, int pos)

{

	memset(leap, false, sizeof(leap));

	leap[xx][yy] = 1;

	queue<Node>p;

	p.push(Node(xx, yy, 0));

	while (p.size())

	{

		Node temp = p.front();

		p.pop();

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

		{

			int tempx = temp.x + dir[i][0];

			int tempy = temp.y + dir[i][1];

			if (tempx >= 1 && tempx <= h&&tempy >= 1 && tempy <= w)

			{

				if (a[tempx][tempy] == 1)continue;

				if (leap[tempx][tempy] == 1)continue;

				if (tempx == x[pos + 1] && tempy == y[pos + 1])

				{

					return temp.t + 1;

				}

				leap[tempx][tempy] = 1;

				p.push(Node(tempx, tempy, temp.t + 1));

			}

		}

	}



}

int main()

{

#ifdef LOCAL

	freopen("C:\\Users\\ΡΡ\\Desktop\\in.txt", "r", stdin);

	//freopen("C:\\Users\\ΡΡ\\Desktop\\out.txt","w",stdout);

#endif // LOCAL

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

	{

		char s[1005];

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

		{

			scanf("%s", s);

			for (int j = 1; j <= w; j++)

			{

				if (s[j - 1] == '.')

					a[i][j] = 0;

				else if (s[j - 1] == 'X')

					a[i][j] = 1;

				else if (s[j - 1] == 'S')

				{

					x[0] = i; y[0] = j;

					a[i][j] = 0;

				}

				else

				{

					a[i][j] = 0;

					int id = s[j - 1] - '0';

					x[id] = i; y[id] = j;

				}

			}

		}

		ans = 0;

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

		{

			ans = ans + work(x[i], y[i], i);

		}

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

	}

	return 0;

}