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

type Result<T> = std::result::Result<T, Box<dyn std::error::Error>>;


fn main() -> Result<()>{
    let file = File::open("data.in");
    let mut br = BufReader::new(file.unwrap());

    let mut x_string = String::new();
    let mut y_string = String::new();
    
    br.read_line(&mut x_string).unwrap();
    br.read_line(&mut y_string).unwrap();
    
    let x: i32 = x_string[0..].trim().parse().unwrap();
    let y: i32 = y_string[0..].trim().parse().unwrap();
    let sum: String = (x + y).to_string();
    // println!("{}", sum);
    fs::write("data.out", sum)
        .expect("Unable to write to file!");
    Ok(())
}