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 <cstdio>
#include <set>
#include <iostream>

const int STEP_NUM = 4;
const int STEP[STEP_NUM][STEP_NUM] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};

const int MAX_SIZE = 1000;
char field[MAX_SIZE + 1][MAX_SIZE + 1];

const int MAXN = 10;
int locationsX[MAXN];
int locationsY[MAXN];
 
int H, W, N;

int get_shortest_distance(int current_HP)
{
	int sx = locationsX[current_HP-1];
	int sy = locationsY[current_HP-1];
	int ex = locationsX[current_HP];
	int ey = locationsY[current_HP];

	bool is_visit[H + 1][W + 1]={};
	
	std::set<std::pair<int,int>> frontier;
	frontier.insert(std::pair<int,int>{sx,sy});
	int nx,ny;
	for(int step=0;step<100000000;step++)
	{
		for(auto p:frontier)
		{
			if(p.first==ex && p.second==ey)	return step;
			is_visit[p.first][p.second] = true;
		}
		std::set<std::pair<int,int>> next_frontier;
		for(auto p:frontier)
		{
			for(int i=0;i<STEP_NUM;i++)
			{
				nx = p.first+STEP[i][0];
				ny = p.second+STEP[i][1];
				if(nx<0 || H<=nx) 		continue;
				if(ny<0 || W<=ny) 		continue;
				if(field[nx][ny]=='X') 	continue;
				if(is_visit[nx][ny]) 	continue;
				next_frontier.insert(std::make_pair(nx,ny));
			}
		}
		frontier = next_frontier;
	}
	return -1;
}

int solve()
{
	int total_step = 0;
	for(int i=1;i<N+1;i++)
		total_step += get_shortest_distance(i);
	return total_step;
}

int main()
{
	scanf("%d %d %d", &H, &W, &N);
	for(int i=0; i<H; i++)
		scanf("%s", field[i]);
	for(int i=0; i<H; i++)
		for(int j=0; j<W; j++)
		{
			int HP=-1;
			if(field[i][j]=='S')	HP=0;
			if(field[i][j]=='1')	HP=1;
			if(field[i][j]=='2')	HP=2;
			if(field[i][j]=='3')	HP=3;
			if(field[i][j]=='4')	HP=4;
			if(field[i][j]=='5')	HP=5;
			if(field[i][j]=='6')	HP=6;
			if(field[i][j]=='7')	HP=7;
			if(field[i][j]=='8')	HP=8;
			if(field[i][j]=='9')	HP=9;
			if(HP!=-1)
			{
				locationsX[HP]=i;
				locationsY[HP]=j;
			}
		}
	printf("%d\n", solve());
	return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <queue>
#include <cstring>
using namespace std;
#define MAX 1005

char JOI[MAX][MAX];
int h,w,n;
int dx[]={0,-1,0,1};
int dy[]={1,0,-1,0};

pair<int, int> goal[10];
bool check(int a,int b){
    return (a>=1&&a<=h&&b>=1&&b<=w);
}

int step[MAX][MAX];
int bfs(const pair<int, int>& st, const pair<int, int>& en){
    queue<pair<int,int> > q;
    q.push(st);
    memset(step, -1, sizeof(step));
    step[st.first][st.second]=0;
    while(!q.empty()){
        pair<int, int> S=q.front(); q.pop();
        int x=S.first;  int y=S.second;
        int stp=step[x][y];
        for(int i=0; i<4; i++){
            int cx=x+dx[i]; int cy=y+dy[i];
            if(check(cx, cy)){
                if(JOI[cx][cy]!='X'&&step[cx][cy]==-1){
                    if(cx==en.first&&cy==en.second) return stp+1;
                    q.push(make_pair(cx, cy));
                    step[cx][cy]=stp+1;
                }
            }
        }
    }
}
int main(){
    cin>>h>>w>>n;
    for(int i=1; i<=h; i++){
        for(int j=1; j<=w; j++){
            cin>>JOI[i][j];
            if(JOI[i][j]=='S') goal[0]=make_pair(i, j);
            else if(JOI[i][j]>='0'&&JOI[i][j]<='9'){
                int x=JOI[i][j]='0';
                goal[x]=make_pair(i, j);
            }
        }
    }
    int ans=0;
    for(int i=0; i<n; i++){
        ans+=bfs(goal[i],goal[i+1]);
    }
    cout<<ans<<endl;
}

C++: # include <iostream>
# include <queue>
# include <cctype>
typedef std::pair<int, int> P;

const int INF = 100000;
const int MAX_H = 1000;
const int MAX_W = 1000;
const int MAX_N = 9;

int dx[4] = { 1,-1,0,0 }, dy[4] = { 0,0,1,-1 };
int h, w, n;
int d[MAX_H][MAX_W];
char ch[MAX_H][MAX_W];
P p[MAX_N + 1];

int bfs(P s, P g) {
	for (int i = 0; i<h; ++i) {
		for (int j = 0; j<w; ++j)
			d[i][j] = INF;
	}
	std::queue<P> que;
	que.push(s);
	d[s.second][s.first] = 0;
	while (!que.empty()) {
		P x = que.front(); que.pop();
		if (x == g)
			break;
		for (int i = 0; i < 4; ++i) {
			int nx = x.first + dx[i];
			int ny = x.second + dy[i];
			if (nx >= 0 && ny >= 0 && nx < w && ny < h && d[ny][nx] == INF && ch[ny][nx] != 'X') {
				que.push(P(nx, ny));
				d[ny][nx] = d[x.second][x.first] + 1;
			}
		}
	}
	return d[g.second][g.first];
}

int solve() {
	int res = 0;
	for (int i = 1; i <= n; ++i) {
		res += bfs(p[i - 1], p[i]);
	}
	return res;
}

int main() {
	std::cin >> h >> w >> n;
	for (int i = 0; i < h; ++i) {
		for (int j = 0; j < w; ++j) {
			std::cin >> ch[i][j];
			if (std::isdigit(ch[i][j])) {
				p[atoi(&ch[i][j])].first = j;
				p[atoi(&ch[i][j])].second = i;
			}
			else if (ch[i][j] == 'S') {
				p[0].first = j;
				p[0].second = i;
			}
		}
	}
	std::cout << solve() << std::endl;
	return 0;
}