1// The Computer Language Benchmarks Game
2// https://benchmarksgame-team.pages.debian.net/benchmarksgame/
3//
4// contributed by the Rust Project Developers
5// contributed by TeXitoi
6// contributed by BurntSushi
7
8use std::io::{self, Read};
9
10macro_rules! regex {
11    ($re:expr) => {
12        ::regex::Regex::new($re).unwrap()
13    };
14}
15
16fn main() {
17    let mut seq = String::with_capacity(50 * (1 << 20));
18    io::stdin().read_to_string(&mut seq).unwrap();
19    let ilen = seq.len();
20
21    seq = regex!(">[^\n]*\n|\n").replace_all(&seq, "").into_owned();
22    let clen = seq.len();
23
24    let variants = vec![
25        regex!("agggtaaa|tttaccct"),
26        regex!("[cgt]gggtaaa|tttaccc[acg]"),
27        regex!("a[act]ggtaaa|tttacc[agt]t"),
28        regex!("ag[act]gtaaa|tttac[agt]ct"),
29        regex!("agg[act]taaa|ttta[agt]cct"),
30        regex!("aggg[acg]aaa|ttt[cgt]ccct"),
31        regex!("agggt[cgt]aa|tt[acg]accct"),
32        regex!("agggta[cgt]a|t[acg]taccct"),
33        regex!("agggtaa[cgt]|[acg]ttaccct"),
34    ];
35    for re in variants {
36        println!("{} {}", re.to_string(), re.find_iter(&seq).count());
37    }
38
39    let substs = vec![
40        (b'B', "(c|g|t)"),
41        (b'D', "(a|g|t)"),
42        (b'H', "(a|c|t)"),
43        (b'K', "(g|t)"),
44        (b'M', "(a|c)"),
45        (b'N', "(a|c|g|t)"),
46        (b'R', "(a|g)"),
47        (b'S', "(c|g)"),
48        (b'V', "(a|c|g)"),
49        (b'W', "(a|t)"),
50        (b'Y', "(c|t)"),
51    ]; // combined into one regex in `replace_all`
52    let seq = replace_all(&seq, substs);
53
54    println!("\n{}\n{}\n{}", ilen, clen, seq.len());
55}
56
57fn replace_all(text: &str, substs: Vec<(u8, &str)>) -> String {
58    let mut replacements = vec![""; 256];
59    let mut alternates = vec![];
60    for (re, replacement) in substs {
61        replacements[re as usize] = replacement;
62        alternates.push((re as char).to_string());
63    }
64
65    let re = regex!(&alternates.join("|"));
66    let mut new = String::with_capacity(text.len());
67    let mut last_match = 0;
68    for m in re.find_iter(text) {
69        new.push_str(&text[last_match..m.start()]);
70        new.push_str(replacements[text.as_bytes()[m.start()] as usize]);
71        last_match = m.end();
72    }
73    new.push_str(&text[last_match..]);
74    new
75}
76