64 lines
1.3 KiB
Go
64 lines
1.3 KiB
Go
package solver
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import (
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"maze-solver/maze"
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"maze-solver/utils"
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)
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type DFSSolver struct {
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visited map[*maze.Node]bool
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}
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func (s *DFSSolver) Solve(m *maze.Maze) *maze.SolvedMaze {
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defer utils.Timer("Turn left algorithm", 2)()
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current, end := m.Nodes[0], m.Nodes[len(m.Nodes)-1]
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s.visited = make(map[*maze.Node]bool, len(m.Nodes))
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for _, node := range m.Nodes {
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s.visited[node] = false
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}
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stack := make([]*maze.Node, 0, len(m.Nodes))
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stack = append(stack, current)
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for current != end {
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s.visited[current] = true
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left_visited, right_visited, up_visited, down_visited := s.wasVisited(current.Left), s.wasVisited(current.Right), s.wasVisited(current.Up), s.wasVisited(current.Down)
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if left_visited && right_visited && up_visited && down_visited {
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// dead end or no more visited nodes
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stack = stack[:len(stack)-1]
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current = stack[len(stack)-1]
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} else {
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if !left_visited {
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current = current.Left
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} else if !down_visited {
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current = current.Down
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} else if !right_visited {
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current = current.Right
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} else if !up_visited {
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current = current.Up
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}
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stack = append(stack, current)
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}
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}
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ret := &maze.SolvedMaze{
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Maze: m,
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Solution: stack,
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}
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return ret
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}
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func (s *DFSSolver) wasVisited(node *maze.Node) bool {
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if node == nil {
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return true
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}
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visited, _ := s.visited[node]
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return visited
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}
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