fun main(args: Array<String>) {
  val X = readInts()
  for (i in 0..4) {
    if (X[i] == 0) {
      println(i + 1)
    }
  }
}

fun myBinarySearch(begin: Int, end: Int, isOk: (key: Int) -> Boolean): Int {
  var ng = begin
  var ok = end

  while (Math.abs(ok - ng) > 1) {
    val mid = (ok + ng) / 2
    if (isOk(mid)) {
      ok = mid
    } else {
      ng = mid
    }
  }

  return ok
}

fun <T> List<T>.myBinarySearch(isOk: (T) -> Boolean): Int {
  return myBinarySearch(-1, size) { index -> isOk(get(index)) }
}

fun <T> Array<T>.myBinarySearch(isOk: (T) -> Boolean): Int {
  return myBinarySearch(-1, size) { index -> isOk(get(index)) }
}

fun readString() = readLine()!!
fun readStrings() = readString().split(" ")
fun readInt() = readString().toInt()
fun readLong() = readString().toLong()
fun readInts() = readStrings().map { it.toInt() }
fun readLongs() = readStrings().map { it.toLong() }
