31 lines
692 B
Rust
31 lines
692 B
Rust
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pub struct LevelLadder {
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curr: usize,
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next: usize,
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}
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impl Iterator for LevelLadder {
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type Item = usize;
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fn next(&mut self) -> Option<Self::Item> {
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let current = self.curr;
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self.curr = self.next;
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self.next = current + self.next;
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// Since there's no endpoint to a Fibonacci sequence, the `Iterator`
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// will never return `None`, and `Some` is always returned.
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Some(current * 30)
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}
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}
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// Returns a Fibonacci sequence generator
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pub fn get_level_ladder() -> LevelLadder {
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LevelLadder { curr: 1, next: 2 }
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}
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#[test]
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fn test_level_ladder() {
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let mut iter = get_level_ladder();
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assert_eq!(iter.next(), Some(30));
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}
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