Module proconio::source

Defines whitespace-splitted token stream wrapping actual stream like stdin.

The main is trait Source. This is implemented to the following two type of source:

1. Read entire source at once. (once::OnceSource)
2. Read source line by line. (line::LineSource)

OnceSource is very fast, while LineSource is handy for local debugging. OnceSource must read entire input before any other work and you must put EOF (Ctrl-D on Unix or Ctrl-Z on Windows) after input. LineSource reads source one by one. Simply press enter to input.

There is another source named auto::AutoSource. AutoSource is OnceSource in release build, is LineSource in debug build. If you use debug build in local testing, LineSource, convenience version is used. In judge server it is compiled in release mode, so OnceSource, faster version is used. This is usually no problem in judging (except interactive problem?).

You can specify the source to be used in input! as follows:

use proconio::source::auto::AutoSource;
use proconio::input;

let source = AutoSource::from("32 54 -23");
input! {
    from source,
    n: u8,
    m: u32,
    l: i32,
}

println!("{} {} {}", n, m, l);
assert_eq!(n, 32);
assert_eq!(m, 54);
assert_eq!(l, -23);

In above example, OnceSource<BufReader<&[u8]>> and LineSource<BufReader<&[u8]>> implements From<&str>, so you can create the source from a string literal. You can create an instance directly from the value of type implementing BufRead by using OnceSource::new() and LineSource::new().

If you use input! macro with no source specified then it uses AutoSource with stdin. So, locally LineSource are used, in the server OnceSource are used. OnceSource and LineSource behaves samely in point of the read result, but, unintentionally, it may differ in a bare possibility. If it should differ, you can manually specify LineSource as source of input!.

Modules

auto	Defines AutoSource.
line
once

Traits

Readable	A trait representing which type can be read from Source.
Source	The main trait. Types implementing this trait can be used for source of input! macro.