use std::{
    io::{stdin, stdout, Read, Write},
    ops::Index,
};

const WIDTH: usize = 1920;
const HEIGHT: usize = 1080;

fn main() {
    let mut oframe = Frame::new();
    loop {
        let iframe = Frame::read(stdin());

        // let diff = oframe.average_area_diff(&iframe, Area::root());
        // eprintln!("{diff:?}");

        oframe.apply_area_diff(Area::root(), diff);

        oframe.write(stdout());
        // oframe = iframe;
    }
}

pub fn decode(f: &mut Frame, area: Area, tree: DiffTree) {
    oframe.apply_area_diff(Area::root(), diff);

} 

pub enum DiffTree {
    Split([Box<DiffTree>; 2]),
    Diff(PixelDiff),
}

pub fn stuff(a: &Frame, b: &Frame, area: Area) -> DiffTree {
    if area.area() == 1 {
        DiffTree::Diff(Frame::diff_pixel(a, b, area.x1, area.y1))
    } else {
        let (aa, ba) = area.split();
        let (at, bt) = (stuff(a, b, aa), stuff(a, b, ba));
        DiffTree::Split([Box::new(at), Box::new(bt)])
    }
}

#[derive(Debug)]
pub struct Frame(Vec<u8>);
#[derive(Debug)]
pub struct PixelDiff([i8; 3]);
#[derive(Debug, Clone, Copy)]
pub struct Area {
    x1: usize,
    y1: usize,
    x2: usize,
    y2: usize,
}

impl Frame {
    pub fn new() -> Self {
        Self(vec![0u8; WIDTH * HEIGHT * 3])
    }
    pub fn read(mut r: impl Read) -> Self {
        let mut f = Frame::new();
        r.read_exact(&mut f.0).unwrap();
        f
    }
    pub fn write(&self, mut w: impl Write) {
        w.write_all(&self.0).unwrap()
    }

    pub fn diff_pixel(a: &Frame, b: &Frame, x: usize, y: usize) -> PixelDiff {
        let o = (x + y * WIDTH) * 3;
        PixelDiff([
            (a.0[o + 0] as i16 - b.0[o + 0] as i16).clamp(i8::MIN as i16, i8::MAX as i16) as i8,
            (a.0[o + 1] as i16 - b.0[o + 1] as i16).clamp(i8::MIN as i16, i8::MAX as i16) as i8,
            (a.0[o + 2] as i16 - b.0[o + 2] as i16).clamp(i8::MIN as i16, i8::MAX as i16) as i8,
        ])
    }

    pub fn apply_area_diff(&mut self, Area { x1, y1, x2, y2 }: Area, p: PixelDiff) {
        for x in x1..x2 {
            for y in y1..y2 {
                let o = (x + y * WIDTH) * 3;
                self.0[o + 0] = self.0[o + 0].saturating_add_signed(p.0[0]);
                self.0[o + 1] = self.0[o + 1].saturating_add_signed(p.0[1]);
                self.0[o + 2] = self.0[o + 2].saturating_add_signed(p.0[2]);
            }
        }
    }
    pub fn average_area_diff(
        &self,
        other: &Frame,
        area @ Area { x1, y1, x2, y2 }: Area,
    ) -> PixelDiff {
        let (mut r, mut g, mut b) = (0i32, 0i32, 0i32);
        for x in x1..x2 {
            for y in y1..y2 {
                let o = (x + y * WIDTH) * 3;
                r += other.0[o + 0] as i32 - self.0[o + 0] as i32;
                g += other.0[o + 1] as i32 - self.0[o + 1] as i32;
                b += other.0[o + 2] as i32 - self.0[o + 2] as i32;
            }
        }
        let a = area.area() as i32;
        PixelDiff([
            (r / a).clamp(i8::MIN as i32, i8::MAX as i32) as i8,
            (g / a).clamp(i8::MIN as i32, i8::MAX as i32) as i8,
            (b / a).clamp(i8::MIN as i32, i8::MAX as i32) as i8,
        ])
    }
}
impl Area {
    pub fn area(&self) -> usize {
        self.width() as usize * self.height() as usize
    }
    pub fn width(&self) -> usize {
        self.x2 - self.x1
    }
    pub fn height(&self) -> usize {
        self.y2 - self.y1
    }
    pub fn root() -> Self {
        Area {
            x1: 0,
            y1: 0,
            x2: WIDTH,
            y2: HEIGHT,
        }
    }
    pub fn split(&self) -> (Self, Self) {
        let Area { x1, y1, x2, y2 } = *self;
        if self.width() > self.height() {
            let xm = (self.x1 + self.x2) / 2;
            (Self { x1, x2: xm, y1, y2 }, Self { x1: xm, x2, y1, y2 })
        } else {
            let ym = (self.y1 + self.y2) / 2;
            (Self { x1, x2, y1, y2: ym }, Self { x1, x2, y1: ym, y2 })
        }
    }
}