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

#include<cstring>

#include<queue>

#define maxn 1002

#define maxc 10

using namespace std;

struct point{

    int r,c;

};

char graph[maxn][maxn];

int len[maxn][maxn];

bool mark[maxn][maxn];

point node[maxc];

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

int main(void){

    int h,w,cheese,tr,tc,answer=0;

    scanf("%d%d%d",&h,&w,&cheese);

    memset(graph,0,sizeof(graph));

    memset(node,0,sizeof(node));

    for(int i=1;i<=h;i++) for(int j=1;j<=w;j++){

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

        while(graph[i][j]==' ' || graph[i][j]=='\n');

        if(graph[i][j]>='0' && graph[i][j]<='9'){

            node[graph[i][j]-'0'].r=i;

            node[graph[i][j]-'0'].c=j;

        }

        else if(graph[i][j]=='S'){

            node[0].r=i;

            node[0].c=j;

        }

    }

    for(int cnt=0;cnt<cheese;cnt++){

        memset(len,0,sizeof(len));

        memset(mark,false,sizeof(mark));

        for(int i=0;i<=h+1;i++){mark[i][0]=true;mark[i][w+1]=true;}

        for(int j=0;j<=w+1;j++){mark[0][j]=true;mark[h+1][j]=true;}

        queue<point> q;

        q.push(node[cnt]);

        len[node[cnt].r][node[cnt].c]=0;

        point ongo,togo;

        while(!q.empty()){

            ongo=q.front();

            q.pop();

            if(mark[ongo.r][ongo.c]) continue;

            mark[ongo.r][ongo.c]=true;

            if(ongo.r==node[cnt+1].r && ongo.c==node[cnt+1].c){

                answer+=len[ongo.r][ongo.c];

                break;

            }

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

                togo.r=ongo.r+dir[i][0];togo.c=ongo.c+dir[i][1];

                if(mark[togo.r][togo.c]==false && graph[togo.r][togo.c]!='X'){

                    len[togo.r][togo.c]=len[ongo.r][ongo.c]+1;

                    q.push(togo);

                }

            }

        }

    }

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

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 7.075694022398972x):
#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;

}