// Slower C++ solution:


#include <iostream>

#include <cstdio>

#include <cstring>

#include <queue>



using namespace std;

const int maxn = 1e3 + 5;

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

int mp[maxn][maxn];

//bool vis[maxn][maxn];

int d[maxn][maxn];

struct point{

    int x,y;

};

int h,w,n;

 int dis = 0;

void bfs(point &p,int cnt)

{

   // memset(vis, 0, sizeof(vis));

    memset(d, 0, sizeof(d));

    queue<point> q;

    q.push(p);

    while (!q.empty()) {

        point t = q.front();q.pop();

        //vis[t.x][t.y] = true;

        if(mp[t.x][t.y] == cnt + 1) {dis += d[t.x][t.y];p.x = t.x,p.y = t.y;return ;}

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

            int tx = t.x + dir[i][0];

            int ty = t.y + dir[i][1];

            if (tx >= 0 && tx < h && ty >= 0 && ty < w && !d[tx][ty] && mp[tx][ty] != -1) {

                q.push({tx,ty});

                d[tx][ty] = 1 + d[t.x][t.y];

            }

        }

    }

}

int main()

{

    while (scanf("%d%d%d",&h,&w,&n) != EOF) {

        getchar();

        char ch;

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

       // int sx,sy;

        point s;

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

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

                scanf("%c",&ch);

                if(ch == 'S') {s.x = i,s.y = j;mp[i][j] = 0;}

                else if(ch == '.') {mp[i][j] = 0;}

                else if(isdigit(ch)) {mp[i][j] = ch - '0';}

            }

            getchar();

        }

       

        dis = 0;

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

            bfs(s,i);

        }

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

    }

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 9.32286123140464x):
#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#