golang力扣leetcode 427.建立四叉树

type Node struct {
  Val         bool
  IsLeaf      bool
  TopLeft     *Node
  TopRight    *Node
  BottomLeft  *Node
  BottomRight *Node
}
func construct(grid [][]int) *Node {
  var dfs func(rowStart, rowEnd, colStart, colEnd int) *Node
  dfs = func(rowStart, rowEnd, colStart, colEnd int) *Node {
    for i := rowStart; i < rowEnd; i++ {
      for j := colStart; j < colEnd; j++ {
        if grid[i][j] != grid[rowStart][colStart] {
          return &Node{
            Val:         true,
            IsLeaf:      false,
            TopLeft:     dfs(rowStart, (rowStart+rowEnd)/2, colStart, (colStart+colEnd)/2),
            TopRight:    dfs(rowStart, (rowStart+rowEnd)/2, (colStart+colEnd)/2, colEnd),
            BottomLeft:  dfs((rowStart+rowEnd)/2, rowEnd, colStart, (colStart+colEnd)/2),
            BottomRight: dfs((rowStart+rowEnd)/2, rowEnd, (colStart+colEnd)/2, colEnd),
          }
        }
      }
    }
    return &Node{
      Val:         grid[rowStart][colStart] == 1,
      IsLeaf:      true,
      TopLeft:     nil,
      TopRight:    nil,
      BottomLeft:  nil,
      BottomRight: nil,
    }
  }
  return dfs(0, len(grid), 0, len(grid))
}