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<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cmath>
#include<algorithm>
#include<queue>
using namespace std;
const int maxn=1100;
const int INF=10000000;
typedef pair<int,int> P;
char s[maxn][maxn];
int d[maxn][maxn];
int H,W,n;
P point[maxn];
int dx[]={-1,0,1,0},dy[]={0,-1,0,1};
int bfs(int sx,int sy,int gx,int gy)
{
    queue<P>que;
    for(int i=0;i<H;i++)
        for(int j=0;j<W;j++)
        d[i][j]=-1;
    que.push(P(sx,sy));
    d[sx][sy]=0;
    while(que.size()){
        P p=que.front(); que.pop();
        if(p.first==gx&&p.second==gy) break;
        for(int i=0;i<4;i++)
        {
            int nx=p.first+dx[i],ny=p.second+dy[i];
            if(nx>=0&&nx<H&&ny>=0&&ny<W&&s[nx][ny]!='X'&&d[nx][ny]==-1){
                que.push(P(nx,ny));
                d[nx][ny]=d[p.first][p.second]+1;
            }
        }
    }
    return d[gx][gy];
}
int main()
{
    while(cin>>H>>W>>n)
    {
        for(int i=0;i<H;i++)
            for(int j=0;j<W;j++)
            cin>>s[i][j];
        int sx,sy,gx,gy;
        for(int i=0;i<H;i++)
        {
            for(int j=0;j<W;j++)
            {
                if(s[i][j]=='S')
                {
                    sx=i; sy=j; break;
                }
            }
        }
        for(int i=0;i<H;i++)
        {
            for(int j=0;j<W;j++)
            {
                if(s[i][j]>='1'&&s[i][j]<='9')
                {
                    int t=s[i][j]-'0';
                    point[t].first=i;
                    point[t].second=j;
                }
            }
        }
        int cnt=0;
        for(int i=1;i<=n;i++){
            gx=point[i].first;
            gy=point[i].second;
            cnt+=bfs(sx,sy,gx,gy);
            sx=gx;
            sy=gy;
        }
        cout<<cnt<<endl;
    }
    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <fstream>
#include <algorithm>
#include <cmath>
#include <deque>
#include <vector>
#include <queue>
#include <string>
#include <cstring>
#include <map>
#include <stack>
#include <set>
#include <sstream>
#define mod 1000000007
#define eps 1e-6
#define ll long long
#define INF 0x3f3f3f3f
#define MEM(x,y) memset(x,y,sizeof(x))
#define Maxn 1005
using namespace std;
struct node
{
    int x,y,step;
};
node now,net;
char mp[Maxn][Maxn];
int vis[Maxn][Maxn];
int dt[][2] = {{0,1},{1,0},{0,-1},{-1,0}};
int h,w,n;
int total;
int startx,starty;
int bfs(char endd)
{
    MEM(vis,0);
    queue<node>q;
    vis[startx][starty]=1;
    q.push({startx,starty,0});
    while(!q.empty())
    {
        now=q.front();
        q.pop();
        if(mp[now.x][now.y]==endd)
        {
            startx=now.x;
            starty=now.y;
            return now.step;
        }
        for(int i=0; i<4; i++)
        {
            net.x=now.x+dt[i][0];
            net.y=now.y+dt[i][1];
            net.step=now.step+1;
            if(!vis[net.x][net.y]&&mp[net.x][net.y]!='X'&&net.x>=0&&net.x<h&&net.y>=0&&net.y<w)
            {
                vis[net.x][net.y]=1;
                q.push(net);
            }
        }
    }
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin>>h>>w>>n;
    for(int i=0; i<h; i++)
        for(int j=0; j<w; j++)
        {
            cin>>mp[i][j];
            if(mp[i][j]=='S')
            {
                startx=i;
                starty=j;
            }
        }
    total=0;
    for(int i=1; i<=n; i++)
    {
        total+=bfs(char(i+'0'));
    }
    cout<<total<<endl;

}

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

#define INF 999999999
#define MAX_X 1000
#define MAX_Y 1000
#define MAX_HEALTH 10
struct status {
	int health;
	int x;
	int y;
	int minutes;
};

queue<status> bfs;
bool checked[MAX_HEALTH+1][MAX_X+1][MAX_Y+1];//health,x,y
//int lastnum[11] = {0,0,0,0,0,0,0,0,0,0};
int maxhp = 0;
///queue???push??????
///??¢??????????????\??????????????¨?????????status?????´?????????????????????
bool PushToQueue(status a) {
	/*for (int i = 0;i < lastnum[a.health];i++) {
		if (checked[i].health == a.health && checked[a.health][i].x == a.x && checked[a.health][i].y == a.y && checked[a.health][i].minutes == a.minutes){
			cout << "health:" << a.health << "/" << i << "/" << lastnum[a.health] << endl;
			return true;
		} 
	}
	checked[a.health][lastnum[a.health]++] = a;*/
	if (checked[a.health][a.x][a.y] == true) return false;
	if (a.health < maxhp) return false;
	bfs.push(a);
	if (a.health > maxhp) {
		maxhp = a.health;
		//cout << "maxhp has changed to " << maxhp << endl;
	}
	checked[a.health][a.x][a.y] = true;
	return true;
}

int main() {
	for (int a = 0;a < 11;a++) {
		for (int b = 0;b < 1000;b++) {
			for (int c = 0;c < 1000;c++) {
				checked[a][b][c] = false;
			}
		}
	}

	int H , W , N;

	cin >> H >> W >> N;
	char data[H][W];
	
	for (int i = 0;i < H;i++) {
		cin >> data[i];
	}
	//cout << "A" << endl;
	//Find 'S'
	for (int y = 0;y < H;y++) {
		for (int x = 0;x < W;x++) {
			if(data[y][x] == 'S') {
				bfs.push((struct status) {1,x,y,0});
				goto getout;
			}
		}
	}


	getout:
	int result = INF;
	for (;;) {
		if (bfs.empty()) break;
		struct status popped = bfs.front();
		bfs.pop();
		//cout << popped.health << "/" << popped.x << "/" << popped.y << "/" << popped.minutes << "/" << endl;
		if (popped.health == N+1) {
			if (popped.minutes < result) {
				result = popped.minutes;
			}
		}
		else {
			for (int x = -1;x < 2;x++) {
				for (int y = -1;y < 2;y++) {
					if(x != 0 && y != 0) continue;
					if (popped.x + x <0 || popped.x + x >= W || popped.y + y < 0 || popped.y + y >= H) continue;
					if (data[popped.y + y][popped.x + x] == 'S'||data[popped.y + y][popped.x + x] == 'X') continue;
					else if (data[popped.y + y][popped.x + x] == '.') {
						PushToQueue((struct status) {popped.health,popped.x + x,popped.y + y,popped.minutes + 1});
					}
					else {
						//cout << "*****************************factory" << endl;
						int factory = data[popped.y + y][popped.x + x] -48 ;
						//cout << data[popped.y + y][popped.x + x]<< endl;
						if (factory == popped.health) {
							//eat
							PushToQueue((struct status) {popped.health + 1,popped.x + x,popped.y + y,popped.minutes + 1});
						}
						else {
							//the mouse doesn't eat.
							PushToQueue((struct status) {popped.health,popped.x + x,popped.y + y,popped.minutes + 1});
						}
					}
				}
			}
		}
	}
	cout << result << endl;
	return 0;
}