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

#include<algorithm>

#include<cstdio>

#include<cstring>

#include<string>

#include<cstdlib>

#include<stack>

#include<queue>

#include <map>

#include<cmath>

#include<vector>

#define MAX_N 1000000

#define INF 0x3f3f3f3f

#define SIZE 1000

using namespace std;







struct note

{

    int x, y;

}start, ende;

typedef pair<int, int> P;

int H, W, N;

char a[1003][1003];

int sum;

int d[1003][1003];

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

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

void bfs(note h, note m)

{

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

    queue<P> que;

    que.push(P(h.x, h.y));

    d[h.x][h.y] = 0;

    while (!que.empty())

    {

        P p = que.front();

        que.pop();

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

        {

            int xx = p.first + dx[i];

            int yy = p.second + dy[i];

            if (xx >= 0 && xx < H && yy >= 0 && yy < W && a[xx][yy] != 'X' && d[xx][yy] == -1)

            {

                d[xx][yy] = d[p.first][p.second] + 1;

                que.push(P(xx, yy));

            }

        }

    }

    sum += d[m.x][m.y];

    start = ende;

}

void solve()

{

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

    {

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

        {

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

            {

                start.x = i;

                start.y = j;

                i = H;

                j = W;

            }

        }

    }

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

    {

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

        {

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

            {

                if (a[i][j] == k + 49)

                {

                    ende.x = i;

                    ende.y = j;

                    bfs(start, ende);

                    i = H;

                    j = W;

                }

            }

        }

    }

    cout << sum << endl;

}

int main()

{

    cin >> H >> W >> N;

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

    {

        cin >> a[i];

    }

    sum = 0;

    solve();

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.6796536324759712x):
#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);

}