fn gen_data(cap: usize) -> Vec<f64> {
    let mut ret = vec![0f64; cap];
    let start = std::time::Instant::now();
    for i in 0..cap {
        ret[i] += 1f64;
    }
    let end = std::time::Instant::now();
    println!("Took {:?} to generate", end - start);
    return ret;
}
fn gen_data2(cap: usize) -> Vec<f64> {
    let mut ret = Vec::with_capacity(cap);
    let start = std::time::Instant::now();
    for i in 0..cap {
        ret.push(1f64);
    }
    let end = std::time::Instant::now();
    println!("Took {:?} to generate", end - start);
    return ret;
}
fn gen_data3(cap: usize) -> Vec<f64> {
    let mut ret = vec![0f64; cap];
    let start = std::time::Instant::now();
    for v in ret.iter_mut() {
        *v += 1f64;
    }
    let end = std::time::Instant::now();
    println!("Took {:?} to generate", end - start);
    return ret;
}

fn main() {
    for _ in 1..10 {
        gen_data(100000);
    }
    println!("");
    for _ in 1..10 {
        gen_data2(100000);
    }
    println!("");
    for _ in 1..10 {
        gen_data3(100000);
    }
    let handle = std::io::stdin();
    let mut in_buf = String::new();
    handle.read_line(&mut in_buf).expect(":(");
}