fun testFunction(input: String, output: String, func: () -> Unit) {
    val oldIn = System.`in`
    val oldOut= System.out
    val inputStream = ByteArrayInputStream(input.toByteArray())
    val outputStream = ByteArrayOutputStream()
    System.setIn(inputStream)
    System.setOut(PrintStream(outputStream))
    func()
    System.setIn(oldIn)
    System.setOut(oldOut)
    assertEquals(output, outputStream.toString().trim())
    inputStream.close()
    outputStream.close()
}

fun testFunction(testCases: Map<String, String>, func: () -> Unit) {
    testCases.forEach { (input, output) ->
        testFunction(input, output, func)
    }
}