// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

const int MAX = 1024;



int h, w, n, maze[MAX][MAX];

int b[15];

int r[] = {1, -1, 0, 0};

int z[] = {0, 0, -1, 1};

int d[MAX][MAX];

int ans = 0;



int readchar() {

    for(;;) {

        int ch = getchar();

        if(ch != '\n' && ch != '\r') return ch;

    }

}



int bfs(int x, int y, int x2, int y2)

{

    //cout << x << y << x2 << y2 << endl;



    queue<int> q;

    q.push(x * 10000 + y);

    while(!q.empty()) {

        int v = q.front();

        q.pop();

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

            int x1 = v / 10000 + r[i];

            int y1 = v % 10000 + z[i];

            if(x1 == x2 && y1 == y2) {

                d[x1][y1] = d[v / 10000][v % 10000] + 1;

                return 0;

            }

            if(x1 >= 0 && y1 >= 0 && x1 < h && y1 < w && maze[x1][y1] != 'X' && d[x1][y1] == -1) {

                 d[x1][y1] = d[v / 10000][v % 10000] + 1;

                 q.push(x1 * 10000 + y1);

            }

        }

    }

    return 0;

}

int main()

{

    cin >> h >> w >> n;

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

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

             maze[i][j] = readchar();

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

            b[0] = i * 10000 + j;

        }

        if(maze[i][j] != 'S' && maze[i][j] != 'X' && maze[i][j] != '.') {

            b[maze[i][j] - '0'] = i * 10000 + j;

        }

    }

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

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

        d[b[i] / 10000][b[i] % 10000] = 0;

        bfs(b[i] / 10000, b[i] % 10000, b[i + 1] / 10000, b[i + 1] % 10000);

        ans += d[b[i + 1] / 10000][ b[i + 1] % 10000];

    }

    cout << ans << endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.248975957848078x):
#include <iostream>

#include <queue>

using namespace std;

const int INF = 100000000;

typedef pair<int,int> Point;

Point AllPoint[1000];

int W,H;

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

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

char map[1000][1000];

int deep[1000][1000];

int N;

void BFS(Point Start,Point Over){

    queue<Point> que;

    int FirstDeep = deep[Start.first][Start.second];

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

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

            deep[i][j] = INF;

        }

    }

    que.push(Start);

    deep[Start.first][Start.second] = FirstDeep;

    while (que.size()){

        Point p = que.front();

        que.pop();

        if (p.first== Over.first&&p.second == Over.second)

            break;

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

            int ix = p.first+x[i];

            int iy = p.second+y[i];

            if (ix>=0&&ix<=H

                &&iy>=0&&iy<=W

                &&deep[ix][iy] == INF

                &&map[ix][iy]!='X'){

                que.push(Point(ix,iy));

                deep[ix][iy] = deep[p.first][p.second]+1;

            }

        }

    }

}







int main(){

    cin >> H >> W;

    cin >> N;

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

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

            cin >> map[i][j];

            if ((int)map[i][j]-48>=1&&(int)map[i][j]-48<=N){

                AllPoint[(int)map[i][j]-48].first = i;

                AllPoint[(int)map[i][j]-48].second = j;



            }

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

                AllPoint[0].first = i;

                AllPoint[0].second = j;

            }

        }

    }

    deep[AllPoint[0].first][AllPoint[0].second] = 0;

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

        BFS(AllPoint[i],AllPoint[i+1]);

    }

    cout << deep[AllPoint[N].first][AllPoint[N].second]<<endl;



    return 0;

}

//#....

//S.##.

//###G.

//#####

//#####



//#S######.#

//......#..#

//.#.##.##.#

//.#........

//##.##.####

//....#....#

//.#######.#

//....#.....

//.####.###.

//....#...G#