LeetCode 729. My Calendar I

Problem Statement

struct MyCalendar {
    events: Vec<Vec<i32>>
}


/**
 * `&self` means the method takes an immutable reference.
 * If you need a mutable reference, change it to `&mut self` instead.
 */
impl MyCalendar {

    fn new() -> Self {
        MyCalendar {
            events: vec![]
        }
    }

    fn book(&mut self, start: i32, end: i32) -> bool {
        if self.events.len() == 0 {
            self.events.push(vec![start, end]);
            return true;
        }
        
        for e in &self.events {
            let (ss, ee) = (e[0], e[1]);
            if start < ee && end > ss {
                return false;
            }
        }

        self.events.push(vec![start, end]);
        return true;
    }
}

/**
 * Your MyCalendar object will be instantiated and called as such:
 * let obj = MyCalendar::new();
 * let ret_1: bool = obj.book(start, end);
 */