new_contents:   def couting_sort(arr):
  	"""Couting_sort
  		Sorting a array which has no element greater than k
  		Complexity: 0(n)
  	"""
  	k = max(arr)
  	temp_arr = [0]*(k+1)
  	for i in range(0,len(arr)):
  		temp_arr[arr[i]]= temp_arr[arr[i]]+1
  	#temp_array[i] is the times the number i appear in arr
  	for i in range(1, k+1):
  		temp_arr[i] = temp_arr[i] + temp_arr[i-1]
  	#temp_array[i] is the number of element less than or equal i in arr
  	result_arr = [0]*len(arr)
  	#creating a result_arr an put the element in a correct positon
  	for i in range(len(arr)-1,-1,-1):
  		result_arr[temp_arr[arr[i]]-1] = arr[i]
  		temp_arr[arr[i]] = temp_arr[arr[i]]-1
  
  	return result_arr 
  
  
  x =couting_sort([1,2,3,4,9,1,2,8,3,5,7,0,9,8,1,7,4,5])
  print (x)
  
subject: Create counting_sort.py