40 lines
689 B
Go
40 lines
689 B
Go
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package list
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import "fmt"
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/*
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+ size isn't really _necessary_ unless O(1) Len is wanted
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+ append doesn't work well on stack
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*/
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type List struct {
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// in practice this would be a constant size, with the compiler knowing the
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// size
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underlying []int
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head, size int
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}
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func New(ii ...int) List {
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l := List{
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underlying: make([]int, ii),
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size: len(ii),
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}
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copy(l.underlying, ii)
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return l
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}
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func (l List) Len() int {
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return l.size
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}
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func (l List) HeadTail() (int, List) {
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if l.size == 0 {
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panic(fmt.Sprintf("can't take HeadTail of empty list"))
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}
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return l.underlying[l.head], List{
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underlying: l.underlying,
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head: l.head + 1,
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size: l.size - 1,
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}
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}
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