用欧拉计划学Rust编程(第79题)

let data = std::fs::read_to_string("keylog.txt").expect("打开文件失败");
let data2 = data.trim().replace("\r", "");
let lines = data2.split("\n");

let mut set: Vec<(&str, &str)> = vec![];
for line in lines {
    let a = &line[..1];
    let b = &line[1..=1];
    let c = &line[2..];
    if !set.contains(&(a, b)) {
        set.push((a, b));
    }
    if !set.contains(&(b, c)) {
        set.push((b, c));
    }
}

println!("digraph G {{");
println!("  rankdir=LR;");
for (a, b) in set {
    println!("  {} -> {};", a, b);
}
println!("}}");

digraph G {
rankdir=LR;
  3 -> 1;
  1 -> 9;
  6 -> 8;
  8 -> 0;
  1 -> 8;
  6 -> 9;
  9 -> 0;
  1 -> 2;
  2 -> 9;
  6 -> 2;
  2 -> 0;
  7 -> 6;
  8 -> 9;
  3 -> 6;
  7 -> 1;
  1 -> 0;
  7 -> 2;
  1 -> 6;
  6 -> 0;
  7 -> 3;
  3 -> 8;
  2 -> 8;
  7 -> 9;
}