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

#include<algorithm>

#include<cstdio>

#include<cstring>

#include<string>

#include<cstdlib>

#include<stack>

#include<queue>

#include <map>

#include<cmath>

#include<vector>

#define MAX_N 1000000

#define INF 0x3f3f3f3f

#define SIZE 1000

using namespace std;







struct note

{

    int x, y;

}start, ende;

typedef pair<int, int> P;

int H, W, N;

char a[1003][1003];

int sum;

int d[1003][1003];

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

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

void bfs(note h, note m)

{

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

    queue<P> que;

    que.push(P(h.x, h.y));

    d[h.x][h.y] = 0;

    while (!que.empty())

    {

        P p = que.front();

        que.pop();

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

        {

            int xx = p.first + dx[i];

            int yy = p.second + dy[i];

            if (xx >= 0 && xx < H && yy >= 0 && yy < W && a[xx][yy] != 'X' && d[xx][yy] == -1)

            {

                d[xx][yy] = d[p.first][p.second] + 1;

                que.push(P(xx, yy));

            }

        }

    }

    sum += d[m.x][m.y];

    start = ende;

}

void solve()

{

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

    {

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

        {

            if (a[i][j] == 'S')

            {

                start.x = i;

                start.y = j;

                i = H;

                j = W;

            }

        }

    }

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

    {

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

        {

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

            {

                if (a[i][j] == k + 49)

                {

                    ende.x = i;

                    ende.y = j;

                    bfs(start, ende);

                    i = H;

                    j = W;

                }

            }

        }

    }

    cout << sum << endl;

}

int main()

{

    cin >> H >> W >> N;

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

    {

        cin >> a[i];

    }

    sum = 0;

    solve();

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 2.5356823293436985x):
#include<iostream>

#include<cstdio>

#include<queue>

#include<cstring>

#include<vector>

#include<set>

using namespace std;

typedef long long ll;

int H,W,N;

char mm[1005][1005];

bool v[1005][1005];

int xx,yy;

struct node{

    int x,y,step;

};

queue<node> que;

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

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

bool check(int x,int  y){

    if(1<=x&&x<=H&&1<=y&&y<=W&&!v[x][y]&&mm[x][y]!='X')return true;

    else return false;

}

int bfs(int g){

    while(!que.empty())que.pop();

    node t;

    t.x=xx;

    t.y=yy;

    t.step=0;

    v[xx][yy]=1;

    que.push(t);

    while(!que.empty()){

        t=que.front();

        que.pop();

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

            int nx=t.x+dx[i];

            int ny=t.y+dy[i];

            if(check(nx,ny)){

                if(mm[nx][ny]==g+'0'){

                    xx=nx;

                    yy=ny;

                    return t.step+1;

                }

                node tt;

                tt.x=nx;

                tt.y=ny;

                tt.step=t.step+1;

                v[nx][ny]=1;

                que.push(tt);

            }

        }

    }

}

int main(){

    while(~scanf("%d%d%d",&H,&W,&N)){

        for(int i=1;i<=H;i++){

            scanf("%s",mm[i]+1);

        }

        for(int i=1;i<=H;i++){

            for(int j=1;j<=W;j++){

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

                    xx=i;

                    yy=j;

                }

            }

        }

        int ans=0;

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

            memset(v,0,sizeof(v));

            ans+=bfs(i);

        }

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

    }

    return 0; 

}