55 lines
1.1 KiB
Go
55 lines
1.1 KiB
Go
package day07
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func SimulateConstruction(root *Node) int {
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working := make(map[rune]*Node)
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done := map[rune]bool{
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0: true,
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}
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elapsed := 0
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for {
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// returns true when no work is left to do.
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if tick(root, working, done) {
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return elapsed
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}
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elapsed++
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}
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}
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func tick(root *Node, working map[rune]*Node, done map[rune]bool) bool {
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complete := true
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// Find candidates, if we need new ones.
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if len(working) < 5 {
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candidates := findCandidates(root, done)
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for _, candidate := range candidates {
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if len(working) >= 5 {
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break
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}
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// if we see a candidate that we can work on, put it in the map.
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if working[candidate.Name] == nil {
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working[candidate.Name] = candidate
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complete = false
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}
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}
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}
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// work on each in-progress node.
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for _, node := range working {
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complete = false
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node.Worked++
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// if we're done, add it to done and delete from worker queue
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// `-4` is exploiting the fact that the rune capital A is value
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// 65 as an integer (and so on)
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if node.Worked >= int(node.Name)-4 {
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done[node.Name] = true
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delete(working, node.Name)
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}
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}
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return complete
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}
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