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

#include<cstdio>

#include<cstring>

#include<iostream>

#include<algorithm>

#define SC(x) scanf("%d",&x);

#define pr(x)  cout << x << endl;

#define mem(arr,v) memset(arr,v,sizeof arr);

#define bug(x) cout << "#x = " << x <<endl;

const int inf = 0x3f3f3f3f;

const int maxn = 1010;

typedef long long ll;

using namespace std;

char Mz[maxn][maxn],c;

bool vis[maxn][maxn];

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

int M,N,C;

int px[10],py[10];

struct node {

	int x,y,step;

};



int bfs(int des,int sx,int sy) {

	mem(vis,0);

	vis[sx][sy] = 1;

	node nod = {sx,sy,0};

	queue<node> q;

	q.push(nod);



	while(!q.empty()) {

		nod =  q.front();

		q.pop();

		

		int x = nod.x, y = nod.y;

		int step =  nod.step;

		

		if(Mz[x][y] == des + '0')

			return step;

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

			int dx = x + dir[i][0];

			int dy = y + dir[i][1];

			if(Mz[dx][dy] == 'X' || Mz[dx][dy] == -1 || vis[dx][dy])	continue;

			nod = {dx,dy,step + 1};

			q.push(nod);

			vis[dx][dy] = 1;

		}

	}

}



int main() {

//	freopen("in.txt","r",stdin);

	cin >> N >> M >> C;

	mem(Mz,-1)

	mem(px,0)  mem(py,0)



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

		for(int j = 1; j <= M ; j++) {

			cin >> c;

			Mz[i][j] = c;

			if(c == '.' || c == 'X')	continue;

			if(c == 'S') px[0] = i, py[0] = j;

			else

				px[c - '0'] = i , py[c - '0'] = j;

		}

	int res = 0;

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

		if(px[i] && py[i]) {

//				dfs(i + 1,px[i],py[i],0);

			res += bfs(i + 1,px[i],py[i]);

		}

	}

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

}

// Faster C++ solution for the same problem (measured speedup: 1.4792407598795354x):
#include <iostream>

#include <stdlib.h>

#include <queue>

#include <cstring>

#define MAX_NUM 1010

using namespace std;

int H, W, N;

bool flag[MAX_NUM][MAX_NUM] = {false};                            //??是否已遍??

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



class Node {

  public:

    Node();

    Node(int x, int y, int step);

    ~Node();

    int x;

    int y;

    int step;

};



Node::Node() {

}



Node::Node(int x, int y, int step) {

    this->x = x;

    this->y = y;

    this->step = step;

}



Node::~Node() {

}



int BFS(char map[][MAX_NUM], int sx, int sy, int ex, int ey) {

    queue<Node> que;                                                  //第一次出?Memory Limit Exceeded,一定不能使用new来?行?建

    Node node(sx, sy, 0);

    que.push(node);

    flag[sx][sy] = true;                                              //将遍?的?点?置?true



    while(!que.empty()) {

        Node cur = que.front();

        que.pop();



        if(cur.x == ex && cur.y == ey) {

            return cur.step;



        } else {

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

                int k = cur.x + dir[i][0];

                int v = cur.y + dir[i][1];



                if(k >= 0 && k < H && v >= 0 && v < W && map[k][v] != 'X' && !flag[k][v]) { //将可到?并且尚未遍?的?点加入?列

                    Node temp(k, v, cur.step + 1);

                    que.push(temp);

                    flag[k][v] = true;

                }

            }

        }

    }



    return -1;

}



int main() {

    int sx, sy, arr[10][2];

    char map[MAX_NUM][MAX_NUM];



    if(cin >> H >> W >> N && H && W) {

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

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

                cin >> map[i][j];



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

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

                    sx = i;

                    sy = j;

                }



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

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

                    arr[index][0] = i;

                    arr[index][1] = j;

                }

            }

        }



        arr[0][0] = sx;

        arr[0][1] = sy;

        int res = 0;



        for(int i = 0; i + 1 <= N; i++) {

            memset(flag, false, sizeof(flag));

            res += BFS(map, arr[i][0], arr[i][1], arr[i + 1][0], arr[i + 1][1]);

        }



        cout << res << endl;

    }



    return 0;

}