input: def bubble_sort(arr): 
      n = len(arr) 
      for i in range(n-1):
          for j in range(0, n-i-1): 
              if arr[j] > arr[j+1] : 
                  arr[j], arr[j+1] = arr[j+1], arr[j] 
  
  arr = [3,7,4,1]
  bubble_sort(arr) 
  print ("Sorted array :") 
  for i in range(len(arr)): 
      print ("%d" %arr[i]),
      
  # Output:
  # Sorted array:
  # 1
  # 3
  # 4
  # 7
output:     n = len(arr) 
      for i in range(n-1):
          for j in range(0, n-i-1): 
              if arr[j] > arr[j+1] : 
                  arr[j], arr[j+1] = arr[j+1], arr[j] 
  
  arr = [3,7,4,1]
  bubble_sort(arr) 
  print ("Sorted array :") 
  for i in range(len(arr)): 
      print ("%d" %arr[i]),