Koden nedan hämtar tal från en textfil (numbers.txt), med varje nytt tal på en egen rad. Programmet skriver sedan ut ett simpelt stam-blad-diagram.
with open( 'numbers.txt' ) as file:
numbers = file.readlines()
numbers = [num.strip() for num in numbers]
numbers.sort(key=int)
tree = {}
for number in numbers:
stem = str( number )[0:-1]
leaf = str( number )[-1]
if stem == '':
stem = '0'
if stem == '-':
stem = '-0'
if stem in tree:
tree[stem] += ' ' + leaf
else:
tree[stem] = leaf
for stem, leafs in tree.items():
print ( stem + '\t|' + leafs)