public/subjects/brackets_matching

brackets_matching

Instructions

Write a program that takes an undefined number of string in arguments. For each argument, if the expression is correctly bracketed, the program prints on the standard output OK followed by a newline ('\n'), otherwise it prints Error followed by a newline.

Symbols considered as brackets are parentheses ( and ), square brackets [ and ] and curly braces { and }. Every other symbols are simply ignored.

An opening bracket must always be closed by the good closing bracket in the correct order. A string which does not contain any bracket is considered as a correctly bracketed.

If there is no argument, the program must print nothing.

For receiving arguments from the command line you should use something like:

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