Arrays #3 : The Dutch National Flag Problem (V1)

dutchFlagPartition.go

func dutchFlagPartition(arr []int, pivotIndex int) []int{
  pivot := arr[pivotIndex]
  for i:= 0 ; i < len(arr) ; i++ {

    for j:= i + 1 ; j < len(arr) ; j++ {
      if arr[j] < pivot {
        arr[i], arr[j] = arr[j], arr[i]
        break;
      }
    }
    
  }
  // Second pass 
  for i:= len(arr) - 1 ; i >= 0 ; i-- {
    for j:= i - 1 ; j >= 0 ; j-- {
      if arr[j] > pivot {
        arr[i], arr[j] = arr[j], arr[i]
        break;
      }
    }
  }

  return arr
}