ppe2/src/codewars/kata_next_bigger_number_same_digits.py

32 lines
914 B
Python

def next_bigger(n):
# get number as digits in list
digits = [int(x) for x in list(str(n))]
# find index of pivot. return -1 if there is no pivot, meaning number is alreadig biggest
pivot = -1
for i in range(1, len(digits)):
if digits[-i] > digits[-i - 1]:
pivot = -i - 1
break
if pivot == -1:
return -1
# find the smallest digit to the right that is bigger than the pivot
right = digits[pivot + 1 :]
swap = right.index(min([x for x in right if x > digits[pivot]]))
# swap pivot with found digit
digits[pivot], digits[len(digits) - len(right) + swap] = (
right[swap],
digits[pivot],
)
# sort right side of new swapped pivot and replace it at the end
right = digits[pivot + 1 :]
right.sort()
digits[pivot + 1 :] = right
# return number
return int("".join([str(x) for x in digits]))