use std::fs::File;
use std::io::{BufReader, BufRead};

fn main() {
    let file = File::open("data.txt").unwrap();
    let reader = BufReader::new(file);
    let lines = reader.lines().map(|line| line.unwrap());
    let res = lines.flat_map(|line| line.split_whitespace());
    println!("{:?}", res);
}