34 lines
840 B
Go
34 lines
840 B
Go
package datastructs
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type ChainElem[T any] struct {
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Elem *T
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Next *ChainElem[T]
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}
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// reachable checks if you can reach elem l when starting from elem f.
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// It detects loops and returns false if it runs into one.
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func reachable[T any](f, l *ChainElem[T]) bool {
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// Map to keep track of nodes already visited
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checks := make(map[*ChainElem[T]]bool)
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for w := f; w != l; w = w.Next {
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if w == nil {
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return false
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}
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// Shortcut: Maps where the value is bool have a default value of false
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// If a key doesn't exist yet the result will thus be false
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if checks[w] {
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return false
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}
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// Set the current elem to true to mark it as visited
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checks[w] = true
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}
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return true
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}
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// emptyElem creates a new ChainElem[T] with empty values.
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func emptyElem[T any]() *ChainElem[T] {
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return &ChainElem[T]{
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Elem: nil,
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Next: nil,
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}
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}
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