golang数独问题

type Parser struct {
   Matrix [9][9]int
   Rows   [9][9]bool
   Cols   [9][9]bool
   Blocks [9][9]bool
   Stop   bool
}

func (p *Parser) Init(matrix [9][9]int) {
   p.Matrix = matrix
   p.Rows = [9][9]bool{}
   p.Cols = [9][9]bool{}
   p.Blocks = [9][9]bool{}
   for i, line := range matrix {
      for j, num := range line {
         if num == 0 {
            continue
         }
         p.Add(i, j, num)
      }
   }
}

func (p *Parser) Add(i, j, num int) {
   p.Rows[i][num-1] = true
   p.Cols[j][num-1] = true
   p.Blocks[convertPosition2BlockID(i, j)][num-1] = true
   p.Matrix[i][j] = num
}

func (p *Parser) Delete(i, j int) {
   num := p.Matrix[i][j]
   p.Rows[i][num-1] = false
   p.Cols[j][num-1] = false
   p.Blocks[convertPosition2BlockID(i, j)][num-1] = false
   p.Matrix[i][j] = 0
}

func (p *Parser) PosStatus(i, j int) [9]bool {
   status1 := p.Rows[i]
   status2 := p.Cols[j]
   status3 := p.Blocks[convertPosition2BlockID(i, j)]
   res := [9]bool{}
   for i := 0; i < 9; i++ {
      res[i] = status1[i] || status2[i] || status3[i]
   }
   return res
}

func (p *Parser) Parse(seq int) {
   if p.Stop {
      return
   }
   if seq == 81 {
      p.Stop = true
      return
   }
   i, j := seq/9, seq%9
   if p.Matrix[i][j] != 0 {
      p.Parse(seq + 1)
      return
   }
   // dfs + 回溯
   for num, ok := range p.PosStatus(i, j) {
      if ok {
         continue
      }
      p.Add(i, j, num+1)
      p.Parse(seq + 1)
      if p.Stop {
         return
      }
      p.Delete(i, j)
   }
}

func convertPosition2BlockID(i, j int) int {
   bRow, bCol := i/3, j/3
   return bRow*3 + bCol
}