// 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: 9.321521403336547x):
#include <iostream>

#include <queue>

#include <string>

#include <cstdio>

#include <cstring>

#include <utility>

using namespace std;

typedef pair<int, int> P;

char maze[1005][1005];

int d[1005][1005];

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

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

int h, w, n, hard; 

int si, sj;

const int INF = 0x3f3f3f3f;

int tot = 0; 



void BFS(int ai, int aj){

    queue<P> que;

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

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

            d[i][j] = INF;

        }

    }

    que.push(P(ai, aj));

    d[ai][aj] = 0;

    while(!que.empty()){

        P a = que.front();

        que.pop();

        int x = a.first, y = a.second;

        if(maze[x][y]-'0' == hard){

            tot += d[x][y];

            si = x; sj = y;

            break;

        }

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

            int dx = x+dirx[i], dy = y+diry[i];

            if(dx>=0 && dx<h && dy>=0 && dy<w && maze[dx][dy]!='X' && d[dx][dy]==INF){

                d[dx][dy] = d[x][y]+1;

                que.push(P(dx, dy));

            }

        }

    }

}



int main(int argc, char const *argv[]){

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

        getchar();

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

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

                scanf("%c", &maze[i][j]);

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

                    si = i; sj = j;

                }

            }

            getchar();

        }

        tot = 0;

        hard = 1;

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

            BFS(si, sj);

            hard++;

        }

        cout << tot << endl;

    }

    return 0;

}