val xmin = -2.0
val xmax = 1.0
val ymin = -1.0
val ymax = 1.0

fun escapes(cr: Double, ci: Double, it: Int): Boolean {
    var zr: Double = 0.0
    var zi: Double = 0.0
    var zrtmp: Double
    
    for(i in (1..it)) {
        // z <- z^2 + c
        zrtmp = zr*zr - zi*zi + cr
        zi = 2*zr*zi + ci
        zr = zrtmp
        if (zr*zr + zi*zi > 4) {
            return true
        }
    }
    
    return false
}

fun main(args: Array<String>) {
    var xstep = args[0].toInt()
    var ystep = args[1].toInt()
    var iters = args[2].toInt()
    var x: Double
    var y: Double
    
    for(yc in 0..(ystep-1)) {
        y = yc*(ymax-ymin)/ystep + ymin
        for(xc in 0..(xstep-1)) {
            x = xc*(xmax-xmin)/xstep + xmin
            if (escapes(x, y, iters)) {
                print(' ')
            } else {
                print('X')
            }
        }
        print('\n')
    }
}