// 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: 6.533283203981703x):
#include <cstdio>

#include <cstring>

#include <queue>

#include <cctype>



using namespace std;



struct State {

    int step;

    int x;

    int y;



    State() {

        step = 0;

        x = 0;

        y = 0;

    }



    State(int step, int x, int y): step(step), x(x), y(y) {}

};



const int MAX_N = 1000;

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

char board[MAX_N][MAX_N];

int W, H, N;

State pos[10];



void init();

void input();

void solve();

int bfs(State from, State to);

void findPossition();



int main() {

#ifdef LOCAL

    freopen("data.in", "r", stdin);

    freopen("data.out", "w", stdout);

#endif

    init();

    input();

    solve();

    return 0;

}



void init() {

}



void input() {

    scanf("%d %d %d", &H, &W, &N);



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

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

    }

}





void solve() {

    int moves = 0;

    findPossition();



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

        moves += bfs(pos[i], pos[i + 1]);

    }



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

}



int bfs(State from, State to) {

    queue<State> que;

    bool visit[H][W];

    State cur = from;



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

        memset(visit[i], false, sizeof(visit[i]));

    }



    que.push(cur);



    while(!que.empty()) {

        cur = que.front();

        que.pop();



        if(visit[cur.x][cur.y]) {

            continue;

        }

        

        visit[cur.x][cur.y] = true;



        if(cur.x == to.x && cur.y == to.y) {

            break;

        }



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

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

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



            if(x < 0 || x >= H || y < 0 || y >= W || visit[x][y] || 'X' == board[x][y]) {

                continue;

            }



            que.push(State(cur.step + 1, x, y));

        }

    }



    return cur.step;

}



void findPossition() {

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

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

            int c = board[i][j];



            if('S' == c) {

                pos[0] = State(0, i, j);

            }



            if(isdigit(c)) {

                pos[c - '0'] = State(0, i, j);

            }

        }

    }

}