Go: // BFS

package main

import (
	"bufio"
	"os"
		"fmt"
	"strconv"
	"strings"
)

var scanner = bufio.NewScanner(os.Stdin)

var p = [15]int{}
var g = [13][4]int {
	// -1は存在しないマス目
	{2,-1,-1,-1},
	{2,5,-1,-1},{0,1,3,6},{2,7,-1,-1},
	{5,-1,-1,-1},{1,4,6,9},{2,5,7,10},{3,6,8,11},{7,-1,-1,-1},
	{5,10,-1,-1},{6,9,11,12},{7,10,-1,-1},
	{10,-1,-1,-1},
}

/*
　  ０ １ ２ ３ ４
 0 |／|／|  |／|／|
 1 |／|　|  |　|／|
 2 |　|　|  |　|　|
 3 |／|　|  |　|／|
 4 |／|／|  |／|／|
*/

var row = [13]int{0,1,1,1,2,2,2,2,2,3,3,3,4}
var col = [13]int{2,1,2,3,0,1,2,3,4,1,2,3,2}

type wolf struct {
	m [13]int
}

type pair struct {
	first wolf
	second int
}

func abs(a int) int {
	if a < 0 {
		return -a
	}
	return a
}

func print_board(board [13]int) {
	fmt.Println("--------------------------")
	fmt.Printf("        [%2d]\n", board[0])
	fmt.Printf("    [%2d][%2d][%2d]\n", board[1], board[2], board[3])
	fmt.Printf("[%2d][%2d][%2d][%2d][%2d]\n", board[4], board[5], board[6], board[7], board[8])
	fmt.Printf("    [%2d][%2d][%2d]\n", board[9], board[10], board[11])
	fmt.Printf("        [%2d]\n", board[12])
	fmt.Println("--------------------------")
}

func main() {
	for scanner.Scan() {
		p1, _ := strconv.Atoi(scanner.Text())
		if p1 == -1 {
			break
		}
		p[0]= p1
		scanner.Scan()
		buf1 := strings.Split(scanner.Text(), " ")
		p2, _ := strconv.Atoi(buf1[0])
		p3, _ := strconv.Atoi(buf1[1])
		p4, _ := strconv.Atoi(buf1[2])
		p[1], p[2], p[3] = p2, p3, p4
		scanner.Scan()
		buf2 := strings.Split(scanner.Text(), " ")
		p5, _ := strconv.Atoi(buf2[0])
		p6, _ := strconv.Atoi(buf2[1])
		p7, _ := strconv.Atoi(buf2[2])
		p8, _ := strconv.Atoi(buf2[3])
		p9, _ := strconv.Atoi(buf2[4])
		p[4], p[5], p[6], p[7], p[8] = p5, p6, p7, p8, p9
		scanner.Scan()
		buf3 := strings.Split(scanner.Text(), " ")
		p10, _ := strconv.Atoi(buf3[0])
		p11, _ := strconv.Atoi(buf3[1])
		p12, _ := strconv.Atoi(buf3[2])
		p[9], p[10], p[11] = p10, p11, p12
		scanner.Scan()
		p13, _ := strconv.Atoi(scanner.Text())
		p[12] = p13
		S := make(map[wolf]struct{})
		st := wolf{}
		for i := 0; i < 13; i++ {
			st.m[i] = p[i]
		}
		Q := make([]pair, 0)
		S[st] = struct{}{}
		Q = append(Q, pair{st, 0})
		yet := true
		for len(Q) > 0 {
			at := Q[0].first
			// print_board(at.m)
			cost := Q[0].second
			Q = Q[1:]
			ok := true
			for i :=1; i < 12; i++ {
				if at.m[i] != i {
					ok = false
				}
			}
			if ok {
				// print_board(at.m)
				yet = false
				fmt.Println(cost)
				break
			}
			now := cost
			for i := 0; i < 13; i++ {
				if at.m[i] != 0 {
					now += abs(row[i]-row[at.m[i]]) + abs(col[i]-col[at.m[i]])
				}
			}
			if now > 20 {
				continue
			}
			for i := 0; i < 13; i++ {
				if at.m[i] == 0 {
					for j := 0; j < 4; j++ {
						if ^g[i][j] != 0 {
							at.m[i], at.m[g[i][j]] = at.m[g[i][j]], at.m[i]
							if _, ok := S[at]; !ok {
								S[at] = struct{}{}
								Q = append(Q, pair{at, cost+1})
							}
							at.m[i], at.m[g[i][j]] = at.m[g[i][j]], at.m[i]
						}
					}
				}
			}
		}
		if yet {
			fmt.Println("NA")
		}
	}
}

C++: #include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>

using namespace std;

inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}
template<class T> inline T sqr(T x) {return x*x;}

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef long long ll;

#define all(a)  (a).begin(),(a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define pb push_back
#define mp make_pair
#define each(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define exist(s,e) ((s).find(e)!=(s).end())
#define range(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n)  range(i,0,n)
#define clr(a,b) memset((a), (b) ,sizeof(a))
#define dump(x)  cerr << #x << " = " << (x) << endl;
#define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;

const double eps = 1e-10;
const double pi  = acos(-1.0);
const ll inf =1LL << 62;

typedef  pair<string,int> P;

map <string,int> ans;

void bfs(void){
	string ini="0123456789ab0";
	P init;
	init.first=ini;
	init.second=0;
	queue<P> q;
	q.push(init);
	while(!q.empty()){
		P cur;
		cur=q.front();q.pop();
	//	cout << cur.first << endl;
		if(cur.second>=11)
			continue;
		
		if(ans.find(cur.first)==ans.end())
			ans[cur.first]=cur.second;
		else
			continue;
		int zero[2]={-1,-1};
		rep(i,13){
			if(zero[0]==-1&&cur.first[i]=='0')
				zero[0]=i;
			else if(zero[1]==-1&&cur.first[i]=='0')
				zero[1]=i;
		}
		rep(i,2){
			string tar;
			P next;
			int check=zero[i];
			if(check%4){
				int d[4]={-4,-1,4,1};
				rep(j,4){
					if(j==0&&(check==1||check==3))
						continue;
					if(j==1&&(check==1||check==9))
						continue;
					if(j==2&&(check==9||check==11))
						continue;
					if(j==3&&(check==3||check==11))
						continue;
					tar=cur.first;
					int index=check+d[j];
					index=max(index,0);
					index=min(index,12);
					swap(tar[check],tar[index]);
					next.first=tar;
					next.second=cur.second+1;
					q.push(next);
				}
			}else{
				int d[4]={2,1,-1,-2};
				tar=cur.first;
				int index=check/4;
				swap(tar[check],tar[check+d[index]]);
				next.first=tar;
				next.second=cur.second+1;
				q.push(next);
			}
		}
	}
	return ;
}

int bfs2(string query){
	map <string,int> ans2;
	P init;
	init.first=query;
	init.second=0;
	queue<P> q;
	q.push(init);
	while(!q.empty()){
		P cur;
		cur=q.front();q.pop();
	//	cout << cur.first << endl;
		if(cur.second>=11)
			continue;
		if(ans.find(cur.first)!=ans.end())
			return cur.second+ans[cur.first];

		if(ans2.find(cur.first)==ans2.end())
			ans2[cur.first]=cur.second;
		else
			continue;
		int zero[2]={-1,-1};
		rep(i,13){
			if(zero[0]==-1&&cur.first[i]=='0')
				zero[0]=i;
			else if(zero[1]==-1&&cur.first[i]=='0')
				zero[1]=i;
		}
		rep(i,2){
			string tar;
			P next;
			int check=zero[i];
			if(check%4){
				int d[4]={-4,-1,4,1};
				rep(j,4){
					if(j==0&&(check==1||check==3))
						continue;
					if(j==1&&(check==1||check==9))
						continue;
					if(j==2&&(check==9||check==11))
						continue;
					if(j==3&&(check==3||check==11))
						continue;
					tar=cur.first;
					int index=check+d[j];
					index=max(index,0);
					index=min(index,12);
					swap(tar[check],tar[index]);
					next.first=tar;
					next.second=cur.second+1;
					q.push(next);
				}
			}else{
				int d[4]={2,1,-1,-2};
				tar=cur.first;
				int index=check/4;
				swap(tar[check],tar[check+d[index]]);
				next.first=tar;
				next.second=cur.second+1;
				q.push(next);
			}
		}
	}
	return -1;
}

int main(void){
	bfs();
	int input[13];
	while(cin >> input[0],input[0]!=-1){
		for(int i=1;i<13;i++)
			cin >> input[i];
		string query="";
		rep(i,13){
			if(input[i]>=10)
				query+=((input[i]-10)+'a');
			else
				query+=(input[i]+'0');
		}
		int answer=bfs2(query);
		if(answer==-1)
			cout << "NA" << endl;
		else
			cout << answer << endl;
	}
	return 0;
}