Johnny has some difficulty memorizing the small prime numbers. So, his computer science teacher has asked him to play with the following puzzle game frequently.
The puzzle is a 3x3 board consisting of numbers from 1 to 9. The objective of the puzzle is to swap the tiles until the following final state is reached:
1 2 3
4 5 6
7 8 9

At each step, Johnny may swap two adjacent tiles if their sum is a prime number. Two tiles are considered adjacent if they have a common edge.
Help Johnny to find the shortest number of steps needed to reach the goal state.

-----Input-----
The first line contains t, the number of test cases (about 50). Then t test cases follow. Each test case consists of a 3x3 table describing a puzzle which Johnny would like to solve.
The input data for successive test cases is separated by a blank line.

-----Output-----
For each test case print a single line containing the shortest number of steps needed to solve the corresponding puzzle. If there is no way to reach the final state, print the number -1.

-----Example-----
Input:
2

7 3 2 
4 1 5 
6 8 9 

9 8 5 
2 4 1 
3 7 6  

Output:
6
-1

-----Output details-----
The possible 6 steps in the first test case are described in the following figure:

Difficulty: UNKNOWN_DIFFICULTY

Starter code:

Solutions:
from collections import deque
primes = {2, 3, 5, 7, 11, 13, 17}
edges = [(0, 3), (0, 1), (1, 2), (1, 4), (2, 5), (3, 4), (3, 6), (4, 5), (4, 7), (5, 8), (6, 7), (7, 8)]
x = [1, 2, 3, 4, 5, 6, 7, 8, 9]
avail = {tuple(x): 0}
q = deque([x])
while q:
	curr = q.popleft()
	for e in edges:
		if curr[e[0]] + curr[e[1]] in primes:
			nxt = curr[0:]
			(nxt[e[0]], nxt[e[1]]) = (nxt[e[1]], nxt[e[0]])
			nxtt = tuple(nxt)
			if nxtt not in avail:
				avail[nxtt] = avail[tuple(curr)] + 1
				q.append(nxt)
t = int(input())
while t:
	inp = input()
	grid = []
	for i in range(3):
		inp = input()
		for j in inp.strip().split(' '):
			grid.append(int(j))
	gridt = tuple(grid)
	if gridt in avail:
		print(avail[gridt])
	else:
		print(-1)
	t -= 1


primes = set([2, 3, 5, 7, 11, 13, 17])
edge = [(0, 3), (0, 1), (1, 2), (1, 4), (2, 5), (3, 4), (4, 5), (3, 6), (4, 7), (5, 8), (6, 7), (7, 8)]
x = list(range(1, 10))
from collections import deque
queue = deque([x])
resource = {tuple(x): 0}
while queue:
	cur = queue.popleft()
	for ele in edge:
		if cur[ele[0]] + cur[ele[1]] in primes:
			curr = cur[0:]
			(curr[ele[0]], curr[ele[1]]) = (curr[ele[1]], curr[ele[0]])
			ref = tuple(curr)
			if ref not in resource:
				resource[tuple(ref)] = resource[tuple(cur)] + 1
				queue.append(curr)
for _ in range(int(input())):
	li = []
	line = input()
	for i in range(3):
		line = input()
		for j in line.split():
			li.append(int(j))
	li = tuple(li)
	if li in resource:
		print(resource[li])
	else:
		print(-1)


prime = [2, 3, 5, 7, 11, 13, 17]
edges = [(0, 3), (0, 1), (1, 2), (1, 4), (2, 5), (3, 4), (3, 6), (4, 5), (4, 7), (5, 8), (6, 7), (7, 8)]
x = (1, 2, 3, 4, 5, 6, 7, 8, 9)
avail = {x: 0}
queue = [x]
while queue:
	current = queue.pop(0)
	for e in edges:
		if current[e[0]] + current[e[1]] in prime:
			nxt = list(current)
			(nxt[e[0]], nxt[e[1]]) = (nxt[e[1]], nxt[e[0]])
			nxt = tuple(nxt)
			if nxt not in avail:
				avail[nxt] = avail[current] + 1
				queue.append(nxt)
for _ in range(int(input())):
	input()
	grid = ()
	for i in range(3):
		grid += tuple(map(int, input().split()))
	print(avail[grid] if grid in avail else -1)


p = [2, 3, 5, 7, 11, 13, 17]
ed = [(0, 3), (0, 1), (1, 2), (1, 4), (2, 5), (3, 4), (3, 6), (4, 5), (4, 7), (5, 8), (6, 7), (7, 8)]
x = (1, 2, 3, 4, 5, 6, 7, 8, 9)
av = {x: 0}
qu = [x]
while qu:
	cur = qu.pop(0)
	for e in ed:
		if cur[e[0]] + cur[e[1]] in p:
			nxt = list(cur)
			(nxt[e[0]], nxt[e[1]]) = (nxt[e[1]], nxt[e[0]])
			nxt = tuple(nxt)
			if nxt not in av:
				av[nxt] = av[cur] + 1
				qu.append(nxt)
for _ in range(int(input())):
	input()
	grid = ()
	for i in range(3):
		grid += tuple(map(int, input().split()))
	print(av[grid] if grid in av else -1)


PRIMES = {3, 5, 7, 11, 13, 17}

class Node:

	def __init__(self, string):
		self.next = None
		self.a = string

	def swap(self, i, j):
		b = self.a[:i] + self.a[j] + self.a[i + 1:j] + self.a[i] + self.a[j + 1:]
		return Node(b)
start_node = Node('123456789')

class Queue:

	def __init__(self):
		self.front = None
		self.back = None

	def enqueue(self, node):
		if self.back is None:
			self.front = self.back = node
		else:
			self.back.next = node
			self.back = node

	def dequeue(self):
		if self.front is None:
			return None
		else:
			node = self.front
			self.front = node.next
			if self.front is None:
				self.back = None
			return node
q = Queue()
q.enqueue(start_node)
di = {start_node.a: 0}

def bfs(q, level):
	if q.front is None:
		return
	q2 = Queue()
	while q.front is not None:
		n = q.dequeue()
		for i in range(8):
			if i % 3 < 2:
				if int(n.a[i]) + int(n.a[i + 1]) in PRIMES:
					b = n.swap(i, i + 1)
					if b.a not in di:
						di[b.a] = level + 1
						q2.enqueue(b)
			if i < 6:
				if int(n.a[i]) + int(n.a[i + 3]) in PRIMES:
					b = n.swap(i, i + 3)
					if b.a not in di:
						di[b.a] = level + 1
						q2.enqueue(b)
	bfs(q2, level + 1)
bfs(q, 0)
for _ in range(int(input())):
	input()
	clue = ''
	for i in range(3):
		clue += ''.join(input().split())
	print(di.get(clue, -1))