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 <algorithm>
#include <cstring>
#include <queue>

using namespace std;

typedef long long ll;
const int MAX = 1005;

struct node{
	int first;
	int second;
	int step;
	node(int _first = 0, int _second = 0, int _step = 0): first(_first), second(_second), step(_step){}
};
 

int h, w;
int n;
char map[MAX][MAX];
bool vis[MAX][MAX];
int cnt = 1, ans = 0;
int dx[4] = {0, 0, 1, -1};
int dy[4] = {1, -1, 0, 0};

bool in(int x, int y){
	return x >= 0 && x < h && y >= 0 && y < w;
}


void bfs(node start){
	vis[start.first][start.second] = true;
	queue<node> que;
	que.push(start);
	while(!que.empty()){
		node now = que.front();
		que.pop();
		//cout << now.first << " " << now.second << " " << now.step << endl;
		if(map[now.first][now.second] - '0' == cnt){
			if(cnt == n){
				//cout << now.step << endl;
				ans = now.step;
				return;
			}
			cnt++;
			while(!que.empty()){
				que.pop();
			}
			que.push(node(now.first, now.second, now.step));
			memset(vis, false, sizeof(vis));
		}
		vis[now.first][now.second] = true;
		for (int i = 0; i < 4; i++){
			int xx = now.first + dx[i];
			int yy = now.second + dy[i];
			if(in(xx, yy) && !vis[xx][yy] && map[xx][yy] != 'X'){
				node temp; temp.first = xx; temp.second = yy;
				temp.step = now.step + 1;
				//cout << temp.step << endl;
				vis[xx][yy] = true;
				que.push(temp);
			}
		}
	}
}




int main(){
	cin >> h >> w >> n;
	node start;
	for (int i = 0; i < h; i++){
		for (int j = 0; j < w; j++){
			cin >> map[i][j];
			if(map[i][j] == 'S'){
				start.first = i; start.second = j;
			}
		}
	}
	start.step = 0;
	bfs(start);
	cout << ans << endl;
	
	return 0;
}

C++: #include <iostream>
#include <queue>
#include <utility>
using namespace std;
int main(void){
    int dx[4]={1,0,-1,0};
    int dy[4]={0,1,0,-1};
    int H,W,N;
    scanf("%d %d %d",&H,&W,&N);
    int x[N+1],y[N+1];
    char po[1919][1919];
    for(int i=0;i<H;i++)scanf("%s",po[i]);
    for(int i=0;i<H;i++)for(int j=0;j<W;j++){
        if(po[i][j]=='S'){x[0]=j;y[0]=i;}
        if(po[i][j]-'1'>=0&&po[i][j]-'0'<=N){y[po[i][j]-'0']=i;x[po[i][j]-'0']=j;}
    }
    int ans=0;
    for(int i=1;i<=N;i++){
    queue<pair<pair<int,int>,int> > buri;
    buri.push(make_pair(make_pair(y[i-1],x[i-1]),0));
    char tinpo[1919][1919];
    for(int i=0;i<H;i++)for(int j=0;j<W;j++)tinpo[i][j]=po[i][j];
    while(1){
        pair<pair<int,int>,int> unko=buri.front();
        buri.pop();
        int unkox=unko.first.second;
        int unkoy=unko.first.first;
        int unkost=unko.second;
        if(unkox==x[i]&&unkoy==y[i]){ans+=unkost;break;}
        if(unkoy>=0&&unkox>=0&&unkoy<H&&unkox<W){if(tinpo[unkoy][unkox]!='X')for(int i=0;i<4;i++){
            if(unkoy+dy[i]>=0&&unkox+dx[i]>=0&&unkoy+dy[i]<H&&unkox+dx[i]<W&&tinpo[unkoy+dy[i]][unkox+dx[i]]!='X')buri.push(make_pair(make_pair(unkoy+dy[i],unkox+dx[i]),unkost+1));
        }
        tinpo[unkoy][unkox]='X';
            
        }
    }
    }
    printf("%d\n",ans);
    return 0;
}

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][16] = {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;
					}
				}
			}
			else{

			}
		}
	}
}


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;
}