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++: //
//  main.cpp
//

#include <algorithm>
#include <array>
#include <iostream>
#include <vector>
#include <limits>
#include <math.h>
#include <queue>
#include <tuple>
#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <memory>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <memory>

// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=0558

using namespace std;

//// #define TEST
//
//#ifdef TEST
//static const string g_SAMPLE = R"(10 10 9
//.X...X.S.X
//6..5X..X1X
//...XXXX..X
//X..9X...X.
//8.X2X..X3X
//...XX.X4..
//XX....7X..
//X..X..XX..
//X...X.XX..
//..X.......)";
//static FILE* g_IN_FP;
//static const char* g_IN_FN = "./in";
//#define scanf(...) fscanf(g_IN_FP, __VA_ARGS__)
//#endif // TEST

int main() {
//#ifdef TEST
//    g_IN_FP = fopen(g_IN_FN, "w");
//    fwrite(g_SAMPLE.c_str(), 1, g_SAMPLE.size(), g_IN_FP);
//    fclose(g_IN_FP);
//    g_IN_FP = fopen(g_IN_FN, "r");
//#endif // TEST
    int H, W, N;
    scanf("%d %d %d", &H, &W, &N);
    vector<vector<char>> field;
    field.reserve(H);
    for (int i = 0; i < H; i++) {
        field.push_back(vector<char>(W, '.'));
    }
    for (int i = 0; i < H; i++) {
        scanf("%s", &field[i][0]);
    }
    vector<pair<int,int>> factories(N+1, pair<int,int>(0,0));
    for (int i = 0; i < H; i++) {
        for (int j = 0; j < W; j++) {
            if (field[i][j] == 'S') {
                factories[0] = pair<int,int>(i,j);
            } else if ('1' <= field[i][j] && field[i][j] <= '0' + N) {
                factories[field[i][j] - '0'] = pair<int,int>(i,j);
            }
        }
    }
    function<int(pair<int,int>,pair<int,int>)> calcDist = [&field, H, W](pair<int,int> start, pair<int,int> end) -> int {
        vector<vector<int>> distMap;
        distMap.reserve(H);
        for (int i = 0; i < H; i++) {
            distMap.push_back(vector<int>(W, numeric_limits<int>::max()));
        }
        queue<pair<int,int>> seeds;
        seeds.push(start);
        distMap[start.first][start.second] = 0;
        while (true) {
//#ifdef TEST
//            for (int i = 0; i < H; i++) {
//                for (int j = 0; j < W; j++) {
//                    if (distMap[i][j] < numeric_limits<int>::max()) {
//                        cout << distMap[i][j];
//                    } else {
//                        cout << "@";
//                    }
//                }
//                cout << endl;
//            }
//            cout << endl;
//#endif // TEST
            pair<int,int> seed = seeds.front();
            seeds.pop();
            int dist = distMap[seed.first][seed.second];
            if (seed == end) {
                return dist;
            }
            using V = pair<int,int>;
            static const vector<V> VECTS = {V{-1,0}, V{1,0}, V{0,-1}, V{0,1}};
            for (V vec : VECTS) {
                V pt(seed.first + vec.first, seed.second + vec.second);
                if (pt.first < 0 || pt.first >= H || pt.second < 0 || pt.second >= W) {
                    continue;
                }
                if (distMap[pt.first][pt.second] != numeric_limits<int>::max()) {
                    continue;
                }
                if (field[pt.first][pt.second] == 'X') {
                    continue;
                }
                seeds.push(pt);
                distMap[pt.first][pt.second] = dist + 1;
            }
        }
        return numeric_limits<int>::max();
    };
    int total = 0;
    for (int i = 1; i <= N; i++) {
        total += calcDist(factories[i-1],factories[i]);
    }
    printf("%d\n",total);
    return 0;
}

C++: #include <queue>
#include <cstring>
#include <iostream>
using namespace std;

const int N = 1111;
const int cx[] = {0, 0, 1, -1}, cy[] = {1, -1, 0, 0};
char maze[N][N];
int step[N][N];
int h, w, n, sx, sy, ans;

int bfs(int cheese){
    memset(step, -1, sizeof(step));
    queue<pair<int, int> > que;
    que.push(make_pair(sx, sy));
    step[sx][sy] = 0;
    while(!que.empty()){
        int x = que.front().first, y = que.front().second;
        que.pop();
        for(int i = 0; i < 4; ++i){
            int nx = x + cx[i], ny = y + cy[i];
            if(nx < 0 || h <= nx || ny < 0 || w <= ny || maze[nx][ny] == 'X' || step[nx][ny] != -1) continue;
            step[nx][ny] = step[x][y] + 1;
            if(maze[nx][ny] - '0' == cheese){
                sx = nx;
                sy = ny;
                return step[nx][ny];
            }
            que.push(make_pair(nx, ny));
        }
    }
    return 0;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    while(cin >> h >> w >> n){
        for(int i = 0; i < h; ++i)
            for(int j = 0; j < w; ++j){
                cin >> maze[i][j];
                if(maze[i][j] == 'S'){
                    sx = i;
                    sy = j;
                }
            }
        ans = 0;
        for(int i = 1; i <= n; ++i)
            ans += bfs(i);
        cout << ans << endl;
    }
    return 0;
}

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

using namespace std;

int h, w;
char F[1024][1024];

int dist(int x1, int y1, int x2, int y2)
{
  int dx[]={1,-1,0,0},dy[]={0,0,1,-1};
  char vis[1024][1024] = {{0}};
  queue<pair<int, int> > q;
  q.push(make_pair(y1*1000+x1, 0)); vis[y1][x1]=1;
  while(!q.empty()) {
    int x=q.front().first%1000, y=q.front().first/1000, s=q.front().second; q.pop();
    if(x==x2 && y==y2) return s;
    for(int i=0; i<4; ++i) {
      int nx=x+dx[i], ny=y+dy[i];
      if(nx<0||ny<0) continue; if(nx>=w||ny>=h) continue;
      if(F[ny][nx]=='X'||vis[ny][nx]) continue;
      vis[ny][nx]=1; q.push(make_pair(ny*1000+nx,s+1));
    }
  }
  return 100000000;
}

int main()
{
  int n, x[10], y[10];
  scanf("%d%d%d", &h, &w, &n);
  for(int i=0; i<h; ++i) {
    scanf("%s", F[i]);
    for(int j=0; j<w; ++j) {
      if(F[i][j]=='S') { x[0]=j; y[0]=i; F[i][j]='.'; }
      else if('0'<=F[i][j]&&F[i][j]<='9') {
	x[F[i][j]-'0']=j; y[F[i][j]-'0']=i; F[i][j]='.';
      }
    }
  }
  int sol=0;
  for(int i=0; i<n; ++i) sol+=dist(x[i],y[i],x[i+1],y[i+1]);
  printf("%d\n", sol);
  return 0;
}