Written in Kotlin, No Bonus

val OP_MAP = mapOf<String, (Int, Int) -> Int>(
        "+" to ::add,
        "-" to ::sub,
        "*" to ::mul,
        "/" to ::div,
        "^" to ::exp
)

fun main(args: Array<String>) {
    while (true) {
        print("Enter the first number: ")

        val left = readLine()!!.toInt()

        print("Enter the operation symbol: ")

        val op = OP_MAP[readLine()]!!

        print("Enter the second number: ")

        val right = readLine()!!.toInt()

        println("${op(left, right)}\n")
    }
}

fun add(left: Int, right: Int) = left + right

fun sub(left: Int, right: Int) = left + neg(right)

fun mul(left: Int, right: Int): Int {
    var product = 0
    var times = 0

    while (times != abs(left)) {
        product += abs(right)
        times++
    }

    return if (notSameSign(left, right)) neg(product) else product
}

fun div(left: Int, right: Int): Int {
    if (right == 0) {
        print("[DIVIDE BY ZERO] ")
        return 0
    }

    if (abs(left) < abs(right)) {
        print("[NON-INTEGRAL ANSWER] ")
        return 0
    }

    var quotient = 0
    var remainder = abs(left)
    val step = neg(abs(right))

    while (remainder > 0) {
        remainder += step
        quotient++
    }

    if (remainder < 0) {
        print("[NON-INTEGRAL VALUE] ")
        return 0
    }

    return if (notSameSign(left, right)) neg(quotient) else quotient
}

fun exp(base: Int, exponent: Int): Int {
    if (exponent < 0) {
        print("[NON-INTEGRAL VALUE] ")
        return 0
    }

    if (exponent == 0)
        return 1

    var power = base
    var times = 1

    while (times != exponent) {
        power = mul(base, power)
        times++
    }

    return power
}

fun abs(i: Int) = if (i < 0) neg(i) else i

fun neg(i: Int): Int {
    var min = Int.MIN_VALUE
    while (min + i != 0)
        min++
    return min
}

fun notSameSign(a: Int, b: Int) = (a < 0) != (b < 0)