RosettaCodeData/Task/Fibonacci-sequence/Rust/fibonacci-sequence-4.rust
2020-02-17 23:21:07 -08:00

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Text

fn fib_tail_recursive(nth: usize) -> usize {
fn fib_tail_iter(n: usize, prev_fib: usize, fib: usize) -> usize {
match n {
0 => prev_fib,
n => fib_tail_iter(n - 1, fib, prev_fib + fib),
}
}
fib_tail_iter(nth, 0, 1)
}