// -*- coding:utf-8-unix -*-

use std::cmp::*;
use std::collections::*;
use std::fs::File;
use std::io::prelude::*;
use std::io::*;
use std::vec;

const INF: i64 = 1223372036854775807;
const MEM_SIZE: usize = 202020;
const MOD: i64 = 1000000007;
use std::cmp::*;
use std::collections::*;
use std::io::stdin;
use std::io::stdout;
use std::io::Write;
#[allow(dead_code)]
fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}
#[allow(dead_code)]
fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}
#[allow(dead_code)]
fn read_vec2<T: std::str::FromStr>(n: u32) -> Vec<Vec<T>> {
    (0..n).map(|_| read_vec()).collect()
}

#[allow(unused_macros)]
macro_rules! p {
    ([$($x:expr), *]) => {{
        let mut f = true;
        $(
            print!("{}{}", if f {""} else {" "}, $x);
            f = false;
        )*
78786    print!("\n");
    }};
    ($x:expr) => {{
        let mut f = true;
        for a in $x.iter() {
            print!("{}{}", if f {""} else {" "}, a);
            f = false;
        }
        print!("\n");
    }};
}
#[allow(dead_code)]
fn readii() -> (i64, i64) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<i64>().unwrap(),
        iter.next().unwrap().parse::<i64>().unwrap(),
    )
}
#[allow(dead_code)]
fn readuu() -> (usize, usize) {
    let mut str = String::new();
    let _ = stdin().read_line(&mut str).unwrap();
    let mut iter = str.split_whitespace();
    (
        iter.next().unwrap().parse::<usize>().unwrap(),
        iter.next().unwrap().parse::<usize>().unwrap(),
    )
}

#[allow(unused_macros)]
macro_rules! debug {
    ($($e:expr),*) => {
        #[cfg(debug_assertions)]
        $({
            let (e, mut err) = (stringify!($e), std::io::stderr());
            writeln!(err, "{} = {:?}", e, $e).unwrap()
        })*
    };
}

fn solve() {
    let (h, w, a, b) = {
        let s = {
            let mut s = String::new(); // バッファを確保
            std::io::stdin().read_line(&mut s).unwrap(); // 一行読む。失敗を無視
            s.trim_right().to_owned() // 改行コードが末尾にくっついてくるので削る
        };

        let mut ws = s.split_whitespace(); // 空白区切りの単語に分解する
        let n: usize = ws.next().unwrap().parse().unwrap(); // イテレータから値を取り出して整数に
        let m: usize = ws.next().unwrap().parse().unwrap();
        let a: usize = ws.next().unwrap().parse().unwrap();
        let b: usize = ws.next().unwrap().parse().unwrap();
        (n, m, a, b)
    };
    let mut vv: Vec<Vec<i64>> = vec![vec![0; (w) as usize]; (h) as usize];
    for i in 0..h as usize {
        for j in 0..w as usize {
            let mut f1 = 0;
            let mut f2 = 0;
            if j < a {
                f1 = 1;
            }
            if i < b {
                f2 = 1;
            }
            vv[i][j] = f1 ^ f2;
        }
    }

    for i in 0..h {
        for j in 0..w {
            print!("{}", vv[i][j]);
        }
        println!("");
    }
    return;
}
fn main() {
    solve()
}


Measured memory_bytes: 9880