output_description: Print the number of cards that face down after all the operations.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N M
attempt: # coding: utf-8
  import re
  import math
  from collections import defaultdict
  from collections import deque
  from fractions import Fraction
  import itertools
  from copy import deepcopy
  import random
  import time
  import os
  import queue
  import sys
  import datetime
  from functools import lru_cache
  
  # @lru_cache(maxsize=None)
  readline = sys.stdin.readline
  sys.setrecursionlimit(2000000)
  # import numpy as np
  alphabet = "abcdefghijklmnopqrstuvwxyz"
  mod = int(10**9 + 7)
  inf = int(10**20)
  
  
  def yn(b):
      if b:
          print("yes")
      else:
          print("no")
  
  
  def Yn(b):
      if b:
          print("Yes")
      else:
          print("No")
  
  
  def YN(b):
      if b:
          print("YES")
      else:
          print("NO")
  
  
  class union_find:
      def __init__(self, n):
          self.n = n
          self.P = [a for a in range(n)]
          self.rank = [0] * n
  
      def find(self, x):
          if x != self.P[x]:
              self.P[x] = self.find(self.P[x])
          return self.P[x]
  
      def same(self, x, y):
          return self.find(x) == self.find(y)
  
      def link(self, x, y):
          if self.rank[x] < self.rank[y]:
              self.P[x] = y
          elif self.rank[y] < self.rank[x]:
              self.P[y] = x
          else:
              self.P[x] = y
              self.rank[y] += 1
  
      def unite(self, x, y):
          self.link(self.find(x), self.find(y))
  
      def size(self):
          S = set()
          for a in range(self.n):
              S.add(self.find(a))
          return len(S)
  
  
  def is_pow(a, b):  # aはbの累乗数か
      now = b
      while now < a:
          now *= b
      if now == a:
          return True
      else:
          return False
  
  
  def getbin(num, size):
      A = [0] * size
      for a in range(size):
          if (num >> (size - a - 1)) & 1 == 1:
              A[a] = 1
          else:
              A[a] = 0
      return A
  
  
  def get_facs(n, mod_=0):
      A = [1] * (n + 1)
      for a in range(2, len(A)):
          A[a] = A[a - 1] * a
          if mod_ > 0:
              A[a] %= mod_
      return A
  
  
  def comb(n, r, mod, fac):
      if n - r < 0:
          return 0
      return (fac[n] * pow(fac[n - r], mod - 2, mod) * pow(fac[r], mod - 2, mod)) % mod
  
  
  def next_comb(num, size):
      x = num & (-num)
      y = num + x
      z = num & (~y)
      z //= x
      z = z >> 1
      num = y | z
      if num >= (1 << size):
          return False
      else:
          return num
  
  
  def get_primes(n, type="int"):
      if n == 0:
          if type == "int":
              return []
          else:
              return [False]
      A = [True] * (n + 1)
      A[0] = False
      A[1] = False
      for a in range(2, n + 1):
          if A[a]:
              for b in range(a * 2, n + 1, a):
                  A[b] = False
      if type == "bool":
          return A
      B = []
      for a in range(n + 1):
          if A[a]:
              B.append(a)
      return B
  
  
  def is_prime(num):
      if num <= 1:
          return False
      i = 2
      while i * i <= num:
          if num % i == 0:
              return False
          i += 1
      return True
  
  
  def ifelse(a, b, c):
      if a:
          return b
      else:
          return c
  
  
  def join(A, c=""):
      n = len(A)
      A = list(map(str, A))
      s = ""
      for a in range(n):
          s += A[a]
          if a < n - 1:
              s += c
      return s
  
  
  def factorize(n, type_="dict"):
      b = 2
      list_ = []
      while b * b <= n:
          while n % b == 0:
              n //= b
              list_.append(b)
          b += 1
      if n > 1:
          list_.append(n)
      if type_ == "dict":
          dic = {}
          for a in list_:
              if a in dic:
                  dic[a] += 1
              else:
                  dic[a] = 1
          return dic
      elif type_ == "list":
          return list_
      else:
          return None
  
  
  def pm(x):
      return x // abs(x)
  
  
  def inputintlist():
      return list(map(int, input().split()))
  
  
  ######################################################################################################
  
  
  H, W = map(int, input().split())
  
  
  ans = (H - 2) * (W - 2)
  print(ans)
  
problem_description: Statement
  
  There is a grid with infinitely many rows and columns. In this grid, there is
  a rectangular region with consecutive N rows and M columns, and a card is
  placed in each square in this region. The front and back sides of these cards
  can be distinguished, and initially every card faces up.
  
  We will perform the following operation once for each square contains a card:
  
    * For each of the following nine squares, flip the card in it if it exists: the target square itself and the eight squares that shares a corner or a side with the target square.
  
  It can be proved that, whether each card faces up or down after all the
  operations does not depend on the order the operations are performed. Find the
  number of cards that face down after all the operations.
samples: [{"input": "2 2", "output": "0\n    \n\nWe will flip every card in any of the four operations. Thus, after all the\noperations, all cards face up.\n\n* * *"}, {"input": "1 7", "output": "5\n    \n\nAfter all the operations, all cards except at both ends face down.\n\n* * *"}, {"input": "314 1592", "output": "496080"}]