#include <algorithm>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <set>
using namespace std;
typedef int State[];
const int maxstate = ;
State st[maxstate], goal;
int dist[maxstate];
const int dx[] = {-, , , };
const int dy[] = {, , -, };
set<int> vis;
/*
void init_lookup_table()
{
vis.clear();
}
int try_to_insert(int s)
{
int v = 0;
for(int i = 0; i < 9; i++)
v = v * 10 + st[s][i];
if(vis.count(v))
return 0;
vis.insert(v);
return 1;
}
*/
const int hashsize = ;
int head[hashsize], Next[maxstate];
void init_lookup_table()
{
memset(head, , sizeof(head));
}
int Hash(State &s)
{
int v = ;
for(int i = ; i < ; i++)
v = v * + s[i];
return v % hashsize;
}
int try_to_insert(int s)
{
int h = Hash(st[s]);
int u = head[h];
while(u)
{
if(memcmp(st[u], st[s], sizeof(st[s])) == )
return ;
u = Next[u];
}
Next[s] = head[h];
head[h] = s;
return ;
}
int bfs()
{
init_lookup_table();
int first = , last = ;
dist[] = ;
while(first < last)
{
State &s = st[first];
if(memcmp(goal, s, sizeof(s)) == )
return first;
int z;
for(z = ; z < ; z++)
if(s[z] == )
break;
int x = z / ;
int y = z % ;
for(int i = ; i < ; i++)
{
int fx = x + dx[i];
int fy = y + dy[i];
int fz = fx * + fy;
if(fx >= && fy >= && fx < && fy < )
{
State &t = st[last];
memcpy(&t, &s, sizeof(s));
t[fz] = s[z];
t[z] = s[fz];
dist[last] = dist[first] + ;
if(try_to_insert(last))
last++;
}
}
first++;
}
return ;
}
int main()
{
for(int i = ; i < ; i++)
scanf("%d", &st[][i]);
for(int i = ; i < ; i++)
scanf("%d", &goal[i]);
int ans = bfs();
if(ans > )
printf("%d\n", dist[ans]);
else
printf("-1\n");
return ;
}
/*
2 6 4 1 3 7 0 5 8
8 1 5 7 3 6 4 0 2
*/