c++ - 以下代码的时间复杂度..？

Question

我对以下代码的时间复杂度感到困惑....

i = 0

   //first row
   if(board[i][0] == win && board[i][1] == win && board[i][2] == win)
      return win;

   //second row
   if(board[i+1][0] == win && board[i+1][1] == win && board[i+1][2] == win)
      return win;

   //third row
   if(board[i+2][0] == win && board[i+2][1] == win && board[i+2][2] == win)
      return win;

   //first col
   if(board[0][i] == win && board[1][i] == win && board[1][i] == win)
      return win;

   //second col
   if(board[0][i+1] == win && board[1][i+1] == win && board[2][i+1] == win)
      return win;

   //third col
   if(board[0][i+2] == win && board[1][i+2] == win && board[2][i+2] == win)
      return win;

      //first diag
   if(board[i][i] == win && board[i+1][i+1] == win && board[i+2][i+2] == win)
      return win;

   //second diag
   if(board[i+2][i] == win && board[i+1][i+1] == win && board[i][i+2] == win)
      return win;

Answer 1

它将以恒定时间运行，即 O(1)，假设 board[M][N] 是一个二维数组。