2014-05-20 23:24:01 -05:00
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// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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extern crate collections;
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2014-05-29 21:03:06 -05:00
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use std::collections::Bitv;
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2014-11-09 23:26:10 -06:00
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use std::num::Float;
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2014-05-20 23:24:01 -05:00
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fn main() {
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// Generate sieve of Eratosthenes for n up to 1e6
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2015-02-18 04:42:01 -06:00
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let n = 1000000_usize;
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2014-11-21 19:47:40 -06:00
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let mut sieve = Bitv::from_elem(n+1, true);
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2014-05-20 23:24:01 -05:00
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let limit: uint = (n as f32).sqrt() as uint;
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2015-01-26 14:46:12 -06:00
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for i in 2..limit+1 {
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2014-05-20 23:24:01 -05:00
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if sieve[i] {
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let mut j = 0;
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while i*i + j*i <= n {
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2014-07-03 16:32:41 -05:00
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sieve.set(i*i+j*i, false);
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2014-05-20 23:24:01 -05:00
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j += 1;
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}
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}
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}
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2015-01-26 14:46:12 -06:00
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for i in 2..n+1 {
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2014-05-20 23:24:01 -05:00
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if sieve[i] {
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}
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}
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}
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