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 <cmath>
#include <algorithm>
#include <queue>

#define INF (1e+9)
#define LLINF (1e+18)
#define LL long long

using namespace std;

typedef struct info{
	int nx;
	int ny;
	int cost;
	int target;
	info(int a,int b,int c,int d){
		nx = a;
		ny = b;
		cost = c;
		target = d;
	}
}info;

bool isNumChar(char c){
	if((0 <= c-48)&&(c-48 <= 9))return true;
	return false;
}

int dx[4] = {0,1,0,-1};
int dy[4] = {1,0,-1,0};

int W,H;
int N;

int sx[16] = {0};
int sy[16] = {0};

char field[1024][1024] = {""};
int record[1024][1024][12] = {0};
bool flag[16] = {false};

queue<info> que;


int ans;



int recordReset(){
	for(int i = 0;i < 1024;i++){
		for(int j = 0;j < 1024;j++){
			for(int k = 0;k < 16;k++){
				record[i][j][k] = INF;
			}
		}
	}
}

int bfs(){
	info now(0,0,0,0);
	info next(0,0,0,0);
	for(int i = 0;i < N;i++){
		next = info(sx[i],sy[i],0,i+1);
		que.push(next);
	}

	recordReset();
	while(!que.empty()){
		now = que.front();
		que.pop();
		if(!flag[now.target]){
			//printf("###(%d,%d):::cost<%d>:::target<%d>\n",now.nx,now.ny,now.cost,now.target);
			if(record[now.nx][now.ny][now.target] > now.cost){
				record[now.nx][now.ny][now.target] = now.cost;
				if((sx[now.target] == now.nx)&&(sy[now.target] == now.ny)){
					flag[now.target] = true;
					//printf("###target<%d> completed\n",now.target);
					ans += record[now.nx][now.ny][now.target];
				}
				else{
					switch(field[now.nx][now.ny]){
					case 'X':
						break;
					default:
						for(int i = 0;i < 4;i++){
							next = info(now.nx + dx[i],now.ny + dy[i],now.cost + 1,now.target);
							que.push(next);
						}
						break;
					}
				}
			}
		}
	}
}


int main (void){
	//while(true){
		scanf("%d%d",&H,&W);
		scanf("%d",&N);
		//if((W == 0)&&(H == 0))break;

		ans = 0;

		//Reset Field
		for(int i = 0;i < 1024;i++){
			for(int j = 0;j < 1024;j++){
				field[j][i] = 'X';
			}
		}

		//Reset Flag
		for(int i = 0;i < 16;i++){
			flag[i] = false;
		}

		//Reading Data
		for(int i = 1;i <= H;i++){
			scanf(" ");
			for(int j = 1;j <= W;j++){
				scanf("%c",&field[j][i]);
				if(isNumChar(field[j][i])){
					sx[field[j][i]-48] = j;
					sy[field[j][i]-48] = i;
					//printf("###<%d>(%d,%d)\n",field[j][i] - 48,sx[field[j][i] - 48],sy[field[j][i] - 48]);

				}
				else if(field[j][i] == 'S'){
					sx[0] = j;
					sy[0] = i;
					//printf("###<S>(%d,%d)\n",j,i);
				}
			}
		}

		//DBG
		/*for(int i = 0;i < N;i++){
			printf("<%d>(%d,%d)\n",i,sx[i],sy[i]);
		}*/

		bfs();

		printf("%d\n",ans);
	//}

	return 0;
}

C++: #include<stdio.h>  
#include<string.h>  
#include<queue>  
using namespace std;  
const int maxn=1005;  
int n,m,k,dx[]={-1,1,0,0},dy[]={0,0,1,-1},vis[maxn][maxn];  
char map[maxn][maxn];  
struct maze  
{  
    int x,y,time;  
};  
maze bfs(int bx,int by,char ch)  
{  
    memset(vis,0,sizeof(vis));  
    queue<maze> q;  
    maze st={bx,by,0};  
    q.push(st);vis[bx][by]=1;  
    while(!q.empty())  
    {  
        st=q.front();q.pop();  
        if(map[st.x][st.y]==ch)  
        {  
            return st;  
        }  
        for(int i=0;i<4;++i)  
        {  
            int tx=st.x+dx[i],ty=st.y+dy[i];  
            if(tx<0||tx>=n||ty<0||ty>=m||map[tx][ty]=='X') 
            {  
                continue;  
            }  
            maze tp={tx,ty,st.time+1};  
            if(!vis[tx][ty])  
            {  
                vis[tx][ty]=1;  
                q.push(tp);  
            }  
        }  
    }  
}  
int main()  
{  
    while(~scanf("%d%d%d",&n,&m,&k))  
    {  
        int bx,by;  
        for(int i=0;i<n;++i)  
        {  
            scanf("%s",map[i]);  
            for(int j=0;j<m;++j)  
            {  
                if(map[i][j]=='S')  
                {  
                    bx=i;by=j;  
                    map[i][j]='0';  
                }  
            }  
        }  
        int ans=0;  
        for(int i=0;i<k;i++)  
        {  
            maze tp=bfs(bx,by,map[bx][by]+1);  
            ans+=tp.time;  
            bx=tp.x;by=tp.y;  
        }  
        printf("%d\n",ans);  
    }  
    return 0;  
}

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

struct data{ int x, y, count; };

const int INF = 10000000;

int w, h, n;
int sx, sy;
int gx, gy;
int vx[] = { 1, 0, -1, 0, };
int vy[] = { 0, 1, 0, -1, };
char field[1001][1001];
int d[1001][1001][11];

int bfs(){

    queue<data> que;

    for (int i = 1; i <= h; i++)
        for (int j = 1; j <= w; j++)
            for (int k = 0; k <= n + 1; k++) d[j][i][k] = INF;

    que.push({ sx, sy, 1 });
    d[sx][sy][1] = 0;
    field[sx][sy] = '.';

    while (que.size()){

        data p = que.front(); que.pop();

        if (p.count == n + 1) break;

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

            int nx = p.x + vx[i], ny = p.y + vy[i], c = p.count;

            if (0 < nx && nx < w + 1 && 0 < ny && ny < h + 1 && field[nx][ny] != 'X'
                && d[nx][ny][c] == INF){

                if (field[nx][ny] != '.' && c == field[nx][ny] - '0'){
                    que.push({ nx, ny, c + 1 });
                    d[nx][ny][c] = d[nx][ny][c + 1] = d[p.x][p.y][c] + 1;
                    continue;
                }

                que.push({ nx, ny, c });
                d[nx][ny][c] = d[p.x][p.y][c] + 1;

            }
        }

    }

    return d[gx][gy][n];
}

int main(void){

    cin >> h >> w >> n;

    for (int i = 1; i <= h; i++){
        for (int j = 1; j <= w; j++){
            cin >> field[j][i];
            if (field[j][i] == 'S'){
                sx = j; sy = i;
            }
            else if (n == field[j][i] - '0'){
                gx = j; gy = i;
            }
        }
    }

    int ans = bfs();

    cout << ans << endl;

}