public/subjects/brackets_matching

brackets_matching

Instructions

Create a program that takes an undefined number of command-line arguments. For each argument, if the expression is correctly bracketed, the program prints OK to the standard output followed by a newline ('\n'), otherwise it prints Error followed by a newline.

All characters are ignored except for the following brackets:

• parentheses ( and ).
• square brackets [ and ].
• curly braces { and }.

Opening brackets must only be closed by the corresponding closing bracket. For example, a curly brace cannot close a square bracket.

A String which does not contain any brackets is considered to be correctly bracketed.

If there are no arguments, the program must print nothing.

You'll need to get the command line arguments somehow, and this will get you started:

fn main() {
    let args: Vec<String> = std::env::args().collect();

    //...
}

Usage

$ cargo run '(johndoe)' | cat -e
OK
$ cargo run '([)]' | cat -e
Error
$ cargo run

$ cargo run '' '{[(0 + 0)(1 + 1)](3*(-1)){()}}' | cat -e
OK
OK