output_description: Print how many black stones there are on the grid after processing all Q
  queries.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N Q
      Query_1
      \vdots
      Query_Q
attempt: N, Q = map(int, input().split())
  Min_x = [-1 for _ in range(N)]  # 一番遠い位置にある黒(0index)
  # Min_x[N-1] = -1
  Min_y = [-1 for _ in range(N)]  # 一番遠い位置にある黒(0index)
  # Min_y[N-1] = -1
  black = (N - 2) ** 2
  a = N - 2
  b = N - 2  # 左上の四角の部分
  for query in range(Q):
      # print(black)
      temp = list(map(int, input().split()))  # 1index #x-=1 #0index
      if temp[0] == 1:  # 上に置く
          w = temp[1] - 1  # 0index
          if w <= b:
              # 左上の更新する四角の中の場合、更新前の値が裏返りに使われる。
              black -= a  # 一番遠い黒-1 (0行目にはない）裏返る。0indexなのでそのまま引いてよい。
              for yoko in range(w, b + 1):  # w~bまで
                  Min_y[yoko] = a
              b = w - 1
          else:
              # 既に更新する四角から外れている場合には既存の値を入れる。
              black -= Min_y[
                  w
              ]  # 一番遠い黒-1 (0行目にはない）裏返る。0indexなのでそのまま引いてよい。
      else:  # 横に置く
          h = temp[1] - 1  # 0index
          if h <= a:
              # 左上の更新する四角の中の場合、更新前の値が裏返りに使われる。
              black -= b  # 一番遠い黒-1 (0行目にはない）裏返る。0indexなのでそのまま引いてよい。
              # print(h,a)
              for tate in range(h, a + 1):  # w~bまで
                  Min_x[tate] = b
              a = h - 1
          else:
              # 既に更新する四角から外れている場合には既存の値を入れる。
              black -= Min_x[
                  h
              ]  # 一番遠い黒-1 (0行目にはない）裏返る。0indexなのでそのまま引いてよい。
      # print("x",Min_x)
      # print("y",Min_y)
      # print("black", black)
  print(black)
  
problem_description: Statement
  
  There is a grid with N rows and N columns of squares. Let (i, j) be the square
  at the i-th row from the top and the j-th column from the left.
  
  Each of the central (N-2) \times (N-2) squares in the grid has a black stone
  on it. Each of the 2N - 1 squares on the bottom side and the right side has a
  white stone on it.
  
  Q queries are given. We ask you to process them in order. There are two kinds
  of queries. Their input format and description are as follows:
  
    * `1 x`: Place a white stone on (1, x). After that, for each black stone between (1, x) and the first white stone you hit if you go down from (1, x), replace it with a white stone.
    * `2 x`: Place a white stone on (x, 1). After that, for each black stone between (x, 1) and the first white stone you hit if you go right from (x, 1), replace it with a white stone.
  
  How many black stones are there on the grid after processing all Q queries?
samples: [{"input": "5 5\n    1 3\n    2 3\n    1 4\n    2 2\n    1 2", "output": "1\n    \n\nAfter each query, the grid changes in the following way:\n\n![Figure](https://img.atcoder.jp/ghi/31ba2cd6b3155b137f0e007299225028.png)\n\n* * *"}, {"input": "200000 0", "output": "39999200004\n    \n\n* * *"}, {"input": "176527 15\n    1 81279\n    2 22308\n    2 133061\n    1 80744\n    2 44603\n    1 170938\n    2 139754\n    2 15220\n    1 172794\n    1 159290\n    2 156968\n    1 56426\n    2 77429\n    1 97459\n    2 71282", "output": "31159505795"}]