use std::collections::BinaryHeap;
use std::iter::Iterator;

fn main() {
    const N: usize = 8;

    for len in 0..N {
        let mut tester = BinaryHeap::with_capacity(len);
        assert_eq!(tester.len(), 0);
        assert!(tester.capacity() >= len);
        for _ in 0..len {
            tester.push(());
        }
        assert_eq!(tester.len(), len);
        assert_eq!(tester.iter().count(), len);
        tester.clear();
    }
}