25 lines
576 B
Rust
25 lines
576 B
Rust
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// -*- rust -*-
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fn ack(m: int, n: int) -> int {
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if m == 0 {
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ret n + 1;
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} else {
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if n == 0 {
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ret ack(m - 1, 1);
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} else { ret ack(m - 1, ack(m, n - 1)); }
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}
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}
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fn main() {
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assert (ack(0, 0) == 1);
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assert (ack(3, 2) == 29);
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assert (ack(3, 4) == 125);
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// This takes a while; but a comparison may amuse: on win32 at least, the
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// posted C version of the 'benchmark' running ack(4,1) overruns its stack
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// segment and crashes. We just grow our stack (to 4mb) as we go.
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// assert (ack(4,1) == 65533);
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} |