func sort(a map[int]int) {
  sorting := true
  for sorting {
    sorting = false
    for i := 0; i < len(a) - 1; i++ {
      if a[i] > a[i+1] {
        a[i], a[i+1] = a[i+1], a[i]
        sorting = true
      }
    }
  }
}