23 lines
576 B
Swift
23 lines
576 B
Swift
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import Foundation
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func vanEckSequence(start: [Int], maxLength: Int) -> [Int] {
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let toCompute = maxLength - start.count
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var seq = start + Array(repeating: 0, count: toCompute)
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// print(seq.count)
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for i in start.count..<maxLength {
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// print("i: \(i)")
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if let prevIndex = seq[0..<(i - 1)].lastIndex(of: seq[i - 1]) {
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seq[i] = (i - 1) - prevIndex
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} else {
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seq[i] = 0
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}
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}
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return seq
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}
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let seq = vanEckSequence(start: [9,12,1,4,17,0,18], maxLength: 30000000)
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// print(seq)
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print(seq.last!)
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