fun main(args: Array<String>) {
    val (H, W, A, B) = listOfInt()
    val S = Array<Array<Int>>(H) { Array<Int>(W) { 0 } }
    for (h in 0 until H) {
        for (w in 0 until W) {
            if (h < B)
                if (w < A) S[h][w] = 0
                else S[h][w] = 1
            else
                if (w < A) S[h][w] = 1
                else S[h][w] = 0
        }
        println(S[h].joinToString(separator = ""))
    }
}
fun next() = readLine()!!
fun listOfString() = next().split(" ")
fun listOfInt(delta: Int = 0) = listOfString().map { Integer.parseInt(it) + delta }