19 lines
305 B
Rust
19 lines
305 B
Rust
use std;
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fn fib(n: int) -> int {
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if n < 2 {
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ret 1;
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} else {
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ret fib(n - 1) + fib(n - 2);
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}
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}
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fn main(args: [str]) {
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let n = if vec::len(args) == 2u {
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option::get(int::from_str(args[1]))
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} else {
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30
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};
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std::io::println(#fmt("%d\n", fib(n)));
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}
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