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

#include <queue>

#include <string.h>

using namespace std;

typedef pair<int, int> P;

int sx,sy,H,W,N;

char map1[1002][1002];

int step[1002][1002];

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

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

void find1(int g){

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

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

        if(map1[i][k] == 'S' || map1[i][k] == (g+48)){

        if(map1[i][k] == 'S') map1[i][k] ='.';

        sx = i; sy = k;

        return ;

    }

}



int bfs(int n)

{

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

    queue <P> que;

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

    step[sx][sy] = 0;

    while(que.size()){

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

        que.pop();

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

            int xn = x + dx[i], yn = y + dy[i];

            if(xn >= 0 && xn < W && yn >= 0 && yn < H && map1[xn][yn] != 'X' && step[xn][yn] == -1)

                {

                    step[xn][yn] = step[x][y] + 1;

                    if(map1[xn][yn] == (n+48))

                        {

                            return step[xn][yn];

                        }

                    que.push(P(xn, yn));

                }

        }

    }

return 0;

}



int main()

{

    cin >> W >> H >> N;

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

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

        cin >> map1[i][k];

    int step = 0;

    find1(0);

    step += bfs(1);

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

    {



        find1(i);

        step += bfs(i+1);

    }

    cout << step << endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.059256784096261x):
#include <iostream>

#include <stdio.h>

#include <deque>



using namespace std;



const int INF = 0x3f3f3f3f;

typedef pair<int, int> P;

int h, w, n;

int sx, sy;

int gx, gy;

char cmap[1000][1000];

int goalSum;

int goal[10];

int d[1000][1000];

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

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



int bfs() {

    int res = 0;

    deque<P> que;

    for (int ci = 0; ci < n; ci++) {  //要?行n次循?，?找n次?点，?次?数?入goal[i], 最后累加起来是res 

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

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

                d[i][j] = INF;

            }

        }

        

        que.push_back(P(sx, sy));

        d[sx][sy] = 0;

        

        while(que.size()) {            

            int x = que.front().first;

            int y = que.front().second;

                        

            if ((int)cmap[x][y] == 49 + ci) {

                goal[ci] = d[x][y];

                sx = x;

                sy = y;

                break;

            }

            

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

                int nx = x + dx[i];

                int ny = y + dy[i];

                if (nx >=0 && nx < h && ny >= 0 && ny < w && cmap[nx][ny] != 'X' && d[nx][ny] == INF) {

                    que.push_back(P(nx, ny));

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

                }

            }    

            que.pop_front();        

        }

        que.clear(); 

        res += goal[ci];

    }

    return res;

}



int main() {

    cin >> h >> w >> n;

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

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

            cin >> cmap[i][j];

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

                sx = i;

                sy = j;

            }

        }

    }

    goalSum = bfs();

    cout << goalSum << endl;

    return 0;

}