use std::{thread::sleep, time::Duration};

fn main() {
    let mut y = 1.5;

    let mut a;

    while y > -1.0 {
        let mut x = -1.5;
        while x < 1.5 {
            a = x * x + y * y - 1.0;

            if a * a * a - x * x * y * y * y < 0.0 {
                print!("{}", "❤️")
            } else {
                print!(" ");
            }

            x += 0.05;
        }

        y -= 0.1;

        sleep(Duration::from_secs_f64(0.15));
        println!();
    }
}

实现效果