pub struct Brackets<'a> {
    stack: Vec<&'a str>,
}

impl<'a> From<&'a str> for Brackets<'a> {
    fn from(input: &'a str) -> Self {
        let mut stack = Vec::new();
        for c in input.split_terminator("").skip(1) { // trick to get each char as a slice
            stack.push(c);
        }

        Brackets { stack }
    }
}

impl<'a> Brackets<'a> {
    pub fn are_balanced(&self) -> bool {
        let mut stack = Vec::new();
        for &slice in &self.stack {
            match slice {
                "(" | "[" | "{" => stack.push(slice),
                ")" | "]" | "}" => {
                    let popped = stack.pop();
                    match popped {
                        Some(")") => {
                            if slice != "(" {
                                return false;
                            };
                        }
                        Some("]") => {
                            if slice != "[" {
                                return false;
                            };
                        }
                        Some("}") => {
                            if slice != "{" {
                                return false;
                            };
                        }
                        _ => return false,
                    }
                }
                _ => continue,
            }
        }

        true
    }
}

fn main() {}