Go: ///
// File:  0558.go
// Author: ymiyamoto
//
// Created on Sun Mar  4 20:58:45 2018
//
package main

import (
	"fmt"
	"strconv"
	"strings"
)

type pos struct {
	x, y int
}

var H, W, N int
var graph [][]string

func wfs(p pos, index int) (int, pos) {
	var q []pos
	dists := make([][]int, H)
	for i := range dists {
		dists[i] = make([]int, W)
	}

	q = append(q, p)
	for len(q) > 0 {
		p := q[0]
		dist := dists[p.x][p.y]
		q = q[1:]

		for _, d := range []pos{{-1, 0}, {1, 0}, {0, -1}, {0, 1}} {
			x := p.x + d.x
			y := p.y + d.y
			if 0 <= x && x < H && 0 <= y && y < W && graph[x][y] != "X" && dists[x][y] == 0 {
				dists[x][y] = dist + 1
				q = append(q, pos{x, y})
			}
		}
	}

	for i := range graph {
		for j := range graph[i] {
			if graph[i][j] == strconv.Itoa(index) {
				return dists[i][j], pos{i, j}
			}
		}
	}

	panic("not found")
}

func main() {
	fmt.Scan(&H, &W, &N)

	var start pos

	graph = make([][]string, H)
	for i := range graph {
		var s string
		fmt.Scan(&s)
		graph[i] = strings.Split(s, "")
		for j := range graph[i] {
			if graph[i][j] == "S" {
				start.x = i
				start.y = j
			}
		}
	}

	count := 0
	for i := 1; i <= N; i++ {
		c, s := wfs(start, i)
		start = s
		count += c
	}

	fmt.Println(count)
}

C++: #include "bits/stdc++.h"
#pragma GCC optimize("Ofast")

// Begin {{{
using namespace std;

#ifndef DEBUG
#define dump(...)
#endif

template <class A, class B> inline bool chmax(A &a, const B &b) { return b > a && (a = b, true); }
template <class A, class B> inline bool chmin(A &a, const B &b) { return b < a && (a = b, true); }

template <class T>
inline vector<T> make_v(const T &initvalue, size_t sz) {
    return vector<T>(sz, initvalue);
}

template <class T, class... Args>
inline auto make_v(const T &initvalue, size_t sz, Args... args) {
    return vector<decltype(make_v<T>(initvalue, args...))>(sz, make_v<T>(initvalue, args...));
}

constexpr int INF = 0x3f3f3f3f;
constexpr int64_t LINF = 0x3f3f3f3f3f3f3f3fLL;

constexpr size_t    operator""_sz(unsigned long long value) { return value; };
constexpr intmax_t  operator""_im(unsigned long long value) { return value; };
constexpr uintmax_t operator""_um(unsigned long long value) { return value; };
// }}} End

constexpr int dy[] = {0, 1, 0, -1, -1, 1, 1, -1}; // {{{
constexpr int dx[] = {1, 0, -1, 0, 1, 1, -1, -1};

inline bool inside(int y, int x, int H, int W) {
    return (y >= 0 && x >= 0 && y < H && x < W);
} // }}}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    size_t H, W, N;
    cin >> H >> W >> N;

    size_t sy, sx;

    vector<tuple<char, size_t, size_t>> vec;
    vector<string> mat(H);
    for (size_t i = 0; i < H; ++i) {
        cin >> mat[i];
        for (size_t j = 0; j < W; ++j) {
            if (mat[i][j] == 'S') {
                sy = i, sx = j;
            } else if (isdigit(mat[i][j])) {
                vec.emplace_back(mat[i][j], i, j);
            }
        }
    }

    sort(vec.begin(), vec.end());

    int64_t res = 0;

    for (auto &vi: vec) {

        queue<pair<int, int>> que;
        que.emplace(sy, sx);

        auto dist = make_v(INF, H, W);
        dist[sy][sx] = 0;

        while (!que.empty()) {
            int y = que.front().first;
            int x = que.front().second;
            que.pop();
            for (size_t i = 0; i < 4; ++i) {
                int ny = y + dy[i];
                int nx = x + dx[i];
                if (inside(ny, nx, H, W) && dist[ny][nx] > dist[y][x] + 1 && mat[ny][nx] != 'X') {
                    que.emplace(ny, nx);
                    dist[ny][nx] = dist[y][x] + 1;
                }
            }
        }

        size_t gy, gx;
        tie(ignore, gy, gx) = vi;

        res += dist[gy][gx];

        sy = gy, sx = gx;
    }

    cout << res << "\n";

    return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<queue>

using namespace std;

#define REP(i,n) for(int i=0;i<(n);i++)
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define INF 1e+7

struct P{
    int x;
    int y;
};

int w,h,n;
char feld[1010][1010];
int d[1010][1010];
int sx,sy,gx,gy;
int dx[4]={0,0,1,-1};
int dy[4]={1,-1,0,0};
int ans=0;
P che[15];


int bfs(){
    REP(i,n){
        P sp=che[i];
        sx=che[i].x;
        sy=che[i].y;
        gx=che[i+1].x;
        gy=che[i+1].y;
        queue<P> que;
        REP(y,h)REP(x,w)d[y][x]=INF;
        que.push(sp);
        d[sy][sx]=0;
        while(!que.empty()){
            P p=que.front();
            que.pop();
            int x=p.x;
            int y=p.y;
            if(x==gx&&y==gy){
                ans+=d[gy][gx];
                break;
            }
            REP(i,4){
                int nx=x+dx[i];
                int ny=y+dy[i];
                if(nx<0||ny<0&&nx>=w&&ny>=h)continue;
                if(feld[ny][nx]!='X'&&d[ny][nx]==INF){
                    P next;
                    next.x=nx;
                    next.y=ny;
                    que.push(next);
                    d[ny][nx]=d[y][x]+1;
                }
            }
        }
    }
    return 0;
}

int main(){
    cin>>h>>w>>n;
    REP(y,h){
        REP(x,w){
            scanf(" %c",&feld[y][x]);
            if(feld[y][x]=='S'){
                che[0].x=x;
                che[0].y=y;
            }else if(feld[y][x]>='1'&&feld[y][x]<='9'){
                char c=feld[y][x];
                che[c-'0'].x=x;
                che[c-'0'].y=y;
            }
        }
    }
    bfs();
    cout<<ans<<endl;
    return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); i++)
#define shosu(n) setprecision(n)
#define INF 999999999
using namespace std;
int h, w, n;
string data[1100];
int main() {
  while (cin >> h >> w >> n) {
    rep(i, h) cin >> data[i];

    pair<int, int> ce[10];
    rep(i, h) rep(j, w) {
      if (data[i][j] == 'S') {
        ce[0] = pair<int, int>(i, j);
      }
      if (isdigit(data[i][j])) {
        ce[data[i][j] - '0'] = pair<int, int>(i, j);
      }
    }
    int sum = 0;
    rep(i, n) {
      int mp[1100][1100];
      rep(i, 1100) rep(j, 1100) mp[i][j] = INF;
      bool used[1100][1100] = {};

      mp[ce[i].first][ce[i].second] = 0;
      used[ce[i].first][ce[i].second] = true;
      queue<pair<int, int>> que;
      que.push(ce[i]);
      while (que.size()) {
        int y = que.front().first;
        int x = que.front().second;
        que.pop();
        int dx[] = {0, 1, 0, -1};
        int dy[] = {1, 0, -1, 0};
        rep(i, 4) {
          int ddy = y + dy[i];
          int ddx = x + dx[i];
          if (ddy >= 0 && ddy < h && ddx >= 0 && ddx < w &&
              data[ddy][ddx] != 'X' && !used[ddy][ddx]) {
            used[ddy][ddx] = true;
            mp[ddy][ddx] = mp[y][x] + 1;
            que.push(pair<int, int>(ddy, ddx));
          }
        }
      }
      sum += mp[ce[i + 1].first][ce[i + 1].second];
    }
    cout << sum << endl;
  }

  return 0;
}