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

#include <cstring>

#include <iostream>

using namespace std;



const int N = 1111;

const int cx[] = {0, 0, 1, -1}, cy[] = {1, -1, 0, 0};

char maze[N][N];

int step[N][N];

int h, w, n, sx, sy, ans;



int bfs(int cheese){

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

    queue<pair<int, int> > que;

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

    step[sx][sy] = 0;

    while(!que.empty()){

        int x = que.front().first, y = que.front().second;

        que.pop();

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

            int nx = x + cx[i], ny = y + cy[i];

            if(nx < 0 || h <= nx || ny < 0 || w <= ny || maze[nx][ny] == 'X' || step[nx][ny] != -1) continue;

            step[nx][ny] = step[x][y] + 1;

            if(maze[nx][ny] - '0' == cheese){

                sx = nx;

                sy = ny;

                return step[nx][ny];

            }

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

        }

    }

    return 0;

}



int main(){

    ios::sync_with_stdio(false);

    cin.tie(NULL);

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

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

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

                cin >> maze[i][j];

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

                    sx = i;

                    sy = j;

                }

            }

        ans = 0;

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

            ans += bfs(i);

        cout << ans << endl;

    }

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 3.0181892067889167x):
#include <bits/stdc++.h>

/*

#include <ext/pb_ds/assoc_container.hpp>

#include <ext/pb_ds/tree_policy.hpp>

#include <ext/rb_tree>

*/

#define mem(x,y) memset(x,y,sizeof(x))

//#define P(x) cout<<#x<<" = "<<x<<endl;

#define PN(x,n) cout<<'{'<<x[0];for(int i=1;i<n;i++)cout<<','<<x[i];cout<<'}'<<endl;

#define RP(i,n) for(int i=0;i<n;i++)

#define RP2(i,a,b) for(int i=a;i<=b;i++)

#define mp make_pair

#define P pair<int,int>

#define pb push_back

#define fi first

#define se second

#define inf 0x3f3f3f3f

#define dinf 1e99

#define OJ

#define ite iterator

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

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

using namespace std;/*

using namespace __gnu_cxx;

using namespace __gnu_pbds;

typedef long long ll;

typedef unsigned long long ull;

typedef tree<int, int, less<int>, rb_tree_tag, tree_order_statistics_node_update> Tree;

const double PI = acos(-1.0);  

const double eps = 1e-5;

const double T = 5; //t of fire

const double delta = 0.99; //decreasing speed of t

const int INF = 1000000000;*/

const int maxn=1005;

bool vis[maxn][maxn];

int d[maxn][maxn];

int ans,n,m,k,sx,sy;

int lx[maxn],ly[maxn],G[maxn][maxn];

char bf;

queue<P> q;

int bfs(int sx,int sy,int ex,int ey){

    mem(vis,0);

    q.push(mp(sx,sy));

    vis[sx][sy] = 1;

    d[sx][sy] = 0;

    while(!q.empty()){

	P u = q.front(); q.pop();

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

	    P v=mp(u.fi+dx[dr],u.se+dy[dr]);

	    if(v.fi<1 || v.se<1 || v.fi>n || v.se>m || vis[v.fi][v.se] || G[v.fi][v.se]) continue;

	    d[v.fi][v.se]=d[u.fi][u.se] + 1;

	    vis[v.fi][v.se] = 1;

	    q.push(v);

	}

    }

    return d[ex][ey];

}

int main(){

    cin>>n>>m>>k;

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

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

	    cin>>bf;

	    if(bf=='.') G[i][j] = 0;

	    else if(bf == 'S') sx = i, sy = j, G[i][j] = 0;

	    else if(bf=='X') G[i][j] = 1;

	    else lx[bf-48] = i, ly[bf-48]=j;

	}

    }

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

	ans += bfs(sx,sy,lx[i],ly[i]);

	sx=lx[i], sy=ly[i];

    }

    cout<<ans<<endl;

    return 0;

}