50 lines
966 B
Go
50 lines
966 B
Go
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package lambda
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func Entries[K comparable, V any](m map[K]V) ([]K, []V) {
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keys := make([]K, 0, len(m))
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vals := make([]V, 0, len(m))
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for k, v := range m {
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keys = append(keys, k)
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vals = append(vals, v)
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}
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return keys, vals
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}
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func Flatten[T any](xss [][]T) []T {
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return Foldl(xss, Merge[T])
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}
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func Merge[T any](a, b []T) []T {
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return append(a, b...)
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}
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//split xs into n groups
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//extra elements will be put in the last array to keep order
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//if len(xs) < n, result will be [][]T{xs}
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func Split[T any](xs []T, n int) [][]T {
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if n == 0 {
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return nil
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}
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groupSize := len(xs) / n
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if groupSize == 0 {
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return [][]T{xs}
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}
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idx := 0
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out := make([][]T, n)
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for i := 0; i < len(xs); i = i + groupSize {
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from := i
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to := i + groupSize
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if idx == (n - 1) {
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to = len(xs)
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}
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if to >= len(xs) {
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to = len(xs)
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out[idx] = append(out[idx], xs[from:to]...)
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return out
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}
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out[idx] = append(out[idx], xs[from:to]...)
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idx = idx + 1
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}
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return out
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}
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