// @EXPECTED_RESULTS@: ACCEPTED, TIME_LIMIT_EXCEEDED
import java.math.BigDecimal
import java.math.MathContext

/**
 * Thinking of the solution was trivial, implementing it was hard. Could not have solved it this way without internet.
 * This is probably not the solution the jury had in mind, but it seems to work.
 * This approximation might need some tweaking to fit the constraints. It might fail or be to slow on larger cases.
 */
fun main() {
  println(System.`in`.bufferedReader().lineSequence().drop(1).first()
            .split(" ").map { BigDecimal(it) }.map { it.pow(3) }.sumOf { it }
            .cuberoot())
}

var ITER: Int = 1000
val mc = MathContext(20)
val THREE = BigDecimal("3", mc)
val ONE = BigDecimal("1", mc)
fun BigDecimal.cuberoot(): BigDecimal {

  // Search for the cube root via the Newton-Raphson loop.
  return (0 until ITER).fold(ONE) { x, _ ->
    x.subtract(
      x.pow(3, mc)
        .subtract(this, mc)
        .divide(THREE.multiply(x.pow(2, mc), mc), mc), mc
              )
  }
}