How to convert list to list of list for adjacent numbers

• i have list [31, 32,33, 1,2,3,4, 11,12,13,14]
• I need to put into adjacent numbers into one list for i, i+1

Expected out [[1,2,3,4], [11,12,13,14], [31, 32,33]]

l = [31, 32,33, 1,2,3,4, 11,12,13,14]
l.sort() #sorted the items
new_l = []
for i in l:
    temp_l = []  # temp list before appending to main list
    if i + 1 in l: # if i + 1 is present append to temp_list
        temp_l.append(i)
    new_l.append(temp_l) # temp_l has to append to main list

My out is wrong : [[1], [2], [3], [], [11], [12], [13], [], [31], [32], []]

>Solution :

You can append an empty sub-list to the output list when the difference between the current number and the last number in the last sub-list in the output list is not 1, and keep appending the current number to the last sub-list of the output list:

l = [31, 32,33, 1,2,3,4, 11,12,13,14]
l.sort()

output = []
for i in l:
    if not output or i - output[-1][-1] != 1:
        output.append([])
    output[-1].append(i)

output becomes:

[[1, 2, 3, 4], [11, 12, 13, 14], [31, 32, 33]]

Demo: https://replit.com/@blhsing/UnimportantValidTelecommunications