#![allow(unused)]
fn main() {
    let a = vec![1,2,3,4];
    let b = a.iter().le(a.iter().skip(1));
    println!("expect true got {}", b);

    let a = vec![1,-99,3,4];
    let b = a.iter().le(a.iter().skip(1));
    println!("expect false got {}", b);

    let a = vec![1,2,-99,4];
    let b = a.iter().le(a.iter().skip(1));
    println!("expect false got {}", b);

    let a = vec![1,2,3,-99];
    let b = a.iter().le(a.iter().skip(1));
    println!("expect false got {}", b);
}