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<iostream>
#include<algorithm>
#include<queue>
using namespace std;
struct k{
    int nx;
    int ny;
    int power;
    int nowans;
};
int fiemin[15][1003][1003];
int main(){
    int h,w,n;
    const int dx[4]={0,1,0,-1},dy[4]={-1,0,1,0};
    char fie[1003][1003];
    for(int i=0;i<15;i++){
        for(int j=0;j<1003;j++){
            for(int k=0;k<1003;k++){
                fiemin[i][j][k]=2100000000;
            }
        }
    }
    for(int j=0;j<1003;j++){
        for(int k=0;k<1003;k++){
            fie[j][k]='X';
        }
    }
    k now;
    queue<k> que;
    scanf("%d %d %d",&h,&w,&n);
    for(int i=0;i<h;i++)
        scanf("%s",&fie[i]);
    for(int i=0;i<h;i++){
        for(int j=0;j<w;j++){
            if(fie[i][j]=='S'){
                now.ny=i,now.nx=j,now.power=0,now.nowans=0;
                fie[i][j]='.';
                goto a;
            }
        }
    }
a:
    que.push(now);
    while(1){
        now=que.front(),que.pop();

        //printf("[%d][%d][%d][%d]\n",now.nx,now.ny,now.nowans,now.power);

        if(now.power==n){
            printf("%d\n",now.nowans);
            break;
        }
        /*
        for(int i=0;i<4;i++){
            if(0<=now.nx+dx[i]&&now.nx+dx[i]<w&&0<=now.ny+dy[i]&&now.ny+dy[i]<h){
                if(fie[now.nx+dx[i]][now.ny+dy[i]]==now.power+1+'0'){
                    if(now.nowans+1<fiemin[now.power+1][now.ny+dy[i][now.nx+dx[i]){
                        while(!que.empty())
                            que.pop();
                        now.nx+=dx[i],now.ny+=dy[i],now.power++,now.nowans++;
                        que.push(now);
                        fiemin[now.power][][]=now.nowans;
                    }
                }
            }
        }
        */

        if(0<=now.ny-1){
            if(fie[now.ny-1][now.nx]==now.power+1+'0'){
                if(now.nowans+1<fiemin[now.power+1][now.ny-1][now.nx]){
                        while (!que.empty())
                            que.pop();
                        now.ny--,now.power++,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.ny++,now.power--,now.nowans--;
                }
            }
            else if(fie[now.ny-1][now.nx]!='X'){
                if(now.nowans+1<fiemin[now.power][now.ny-1][now.nx]){
                        now.ny--,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.ny++,now.nowans--;
                }
            }
        }
        if(now.nx+1<w){
            if(fie[now.ny][now.nx+1]==now.power+1+'0'){
                if(now.nowans+1<fiemin[now.power+1][now.ny][now.nx+1]){
                        while (!que.empty())
                            que.pop();
                        now.nx++,now.power++,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.nx--,now.power--,now.nowans--;
                }
            }
            else if(fie[now.ny][now.nx+1]!='X'){
                if(now.nowans+1<fiemin[now.power][now.ny][now.nx+1]){
                        now.nx++,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.nx--,now.nowans--;
                }
            }
        }
        if(now.ny+1<h){
            if(fie[now.ny+1][now.nx]==now.power+1+'0'){
                if(now.nowans+1<fiemin[now.power+1][now.ny+1][now.nx]){
                        while (!que.empty())
                            que.pop();
                        now.ny++,now.power++,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.ny--,now.power--,now.nowans--;
                }
            }
            else if(fie[now.ny+1][now.nx]!='X'){
                if(now.nowans+1<fiemin[now.power][now.ny+1][now.nx]){
                        now.ny++,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.ny--,now.nowans--;
                }
            }
        }
        if(0<=now.nx-1){
            if(fie[now.ny][now.nx-1]==now.power+1+'0'){
                if(now.nowans+1<fiemin[now.power+1][now.ny][now.nx-1]){
                        while (!que.empty())
                            que.pop();
                        now.nx--,now.power++,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.nx++,now.power--,now.nowans--;
                }
            }
            else if(fie[now.ny][now.nx-1]!='X'){
                if(now.nowans+1<fiemin[now.power][now.ny][now.nx-1]){
                        now.nx--,now.nowans++;
                        que.push(now);
                        fiemin[now.power][now.ny][now.nx]=now.nowans;
                        now.nx++,now.nowans--;
                }
            }
        }
    }
    return 0;
}

C++: #include<iostream>
#include<string>
#include<queue>
using namespace std;
char map[1010][1010];
int n,m,k,sum=0;
struct node{
	int x,y;
}a[10010];
int bfs(int sx,int sy,int ex,int ey)
{
	int head=1,tail=2,f[4][2]={0,1,0,-1,1,0,-1,0};
	int xx[1010],yy[1010],s[1010];
	xx[head]=sx;
	yy[head]=sy;
	s[head]=0;
	int maxx=0;
	while(head<tail)
	{
		if(xx[head]==ex&&yy[head]==ey)
		{
			maxx=s[head];
			break;
		}
		for(int i=0;i<4;i++)
		{
			int tx=xx[head]+f[i][0];
			int ty=yy[head]+f[i][1];
			if(tx<1||tx>n||ty<1||ty>m||map[tx][ty]=='X') continue;
			xx[tail]=tx;
			yy[tail]=ty;
			s[tail]=s[head]+1;
			tail++;
		}
		head++;
	}
	return maxx;
}
int main()
{
	cin>>n>>m>>k;
	string s[1010];
	for(int i=1;i<=n;i++)
	cin>>s[i];
	int time=2;
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=m;j++)
		{
			map[i][j]=s[i][j];
			if(map[i][j]=='S')
			{
				a[0].x=i;
				a[0].y=j;
			}
			if(map[i][j]>='1'&&map[i][j]<='9')
			{
				a[map[i][j]-48].x=i;
				a[map[i][j]-48].y=j;
			}
		}
	}
	for(int i=1;i<=k;i++)
	{
		sum+=bfs(a[i-1].x,a[i-1].y,a[i].x,a[i].y);
	}
	cout<<sum;
	return 0;
}