13 lines
304 B
Dart
13 lines
304 B
Dart
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class CollatzConjecture {
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int steps(int start) {
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if (start < 1)
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throw new ArgumentError('Only positive integers are allowed');
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if (start == 1) return 0;
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if (start.isEven) {
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return 1 + this.steps(start ~/= 2);
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} else {
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return 1 + this.steps(start * 3 + 1);
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}
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}
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}
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