// Slower C++ solution:
//

//  AOJ 0558 Chees

//

//  Created by TaoSama on 2015-02-20

//  Copyright (c) 2014 TaoSama. All rights reserved.

//

#include <algorithm>

#include <cctype>

#include <cmath>

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <iomanip>

#include <iostream>

#include <map>

#include <queue>

#include <string>

#include <set>

#include <vector>

#define CLR(x,y) memset(x, y, sizeof(x))



using namespace std;

const int INF = 0x3f3f3f3f;

const int MOD = 1e9 + 7;

const int N = 1e5 + 10;



struct Point {

	int x, y;

	Point(int x = 0, int y = 0): x(x), y(y) {}

} c[15];

int n, m, k, dp[1005][1005];

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

char a[1005][1005];



int bfs(int x) {

	memset(dp, 0x3f, sizeof dp);

	queue <Point> q; q.push(c[x - 1]);

	dp[c[x - 1].x][c[x - 1].y] = 0;

	while(!q.empty()) {

		Point cur = q.front(); q.pop();

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

			Point nxt(cur.x + d[i][0], cur.y + d[i][1]);

			if(nxt.x < 1 || nxt.x > n || nxt.y < 1 || nxt.y > m

			        || a[nxt.x][nxt.y] == 'X') continue;

			if(dp[nxt.x][nxt.y] == INF) {

				dp[nxt.x][nxt.y] = dp[cur.x][cur.y] + 1;

				q.push(nxt);

			}

		}

	}

	return dp[c[x].x][c[x].y];

}

int main() {

#ifdef LOCAL

	freopen("in.txt", "r", stdin);

//	freopen("out.txt","w",stdout);

#endif

	ios_base::sync_with_stdio(0);



	while(cin >> n >> m >> k) {

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

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

				cin >> a[i][j];

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

					c[0].x = i, c[0].y = j;

				if(isdigit(a[i][j]))

					c[a[i][j] - '0'].x = i, c[a[i][j] - '0'].y = j;

			}

		}

		int ans = 0;

		for(int i = 1; i <= k; ++i)

			ans += bfs(i);

		cout << ans << endl;

	}

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.500687189861935x):
#include <cstdio>

#include <cstring>

#include <queue>

#include <cctype>



using namespace std;



struct State {

    int step;

    int x;

    int y;



    State() {

        step = 0;

        x = 0;

        y = 0;

    }



    State(int step, int x, int y): step(step), x(x), y(y) {}

};



const int MAX_N = 1000;

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

char board[MAX_N][MAX_N];

int W, H, N;

State pos[10];



void init();

void input();

void solve();

int bfs(State from, State to);

void findPossition();



int main() {

#ifdef LOCAL

    freopen("data.in", "r", stdin);

    freopen("data.out", "w", stdout);

#endif

    init();

    input();

    solve();

    return 0;

}



void init() {

}



void input() {

    scanf("%d %d %d", &H, &W, &N);



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

        scanf("%s", board[i]);

    }

}





void solve() {

    int moves = 0;

    findPossition();



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

        moves += bfs(pos[i], pos[i + 1]);

    }



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

}



int bfs(State from, State to) {

    queue<State> que;

    bool visit[H][W];

    State cur = from;



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

        memset(visit[i], false, sizeof(visit[i]));

    }



    que.push(cur);



    while(!que.empty()) {

        cur = que.front();

        que.pop();



        if(visit[cur.x][cur.y]) {

            continue;

        }

        

        visit[cur.x][cur.y] = true;



        if(cur.x == to.x && cur.y == to.y) {

            break;

        }



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

            int x = cur.x + dir[i][0];

            int y = cur.y + dir[i][1];



            if(x < 0 || x >= H || y < 0 || y >= W || visit[x][y] || 'X' == board[x][y]) {

                continue;

            }



            que.push(State(cur.step + 1, x, y));

        }

    }



    return cur.step;

}



void findPossition() {

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

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

            int c = board[i][j];



            if('S' == c) {

                pos[0] = State(0, i, j);

            }



            if(isdigit(c)) {

                pos[c - '0'] = State(0, i, j);

            }

        }

    }

}