Largest Number After Digit Swaps by Parity.py

class Solution:
    def largestInteger(self, num: int):
        n = len(str(num))
        arr = [int(i) for i in str(num)]
        odd, even = [], []
        for i in arr:
            if i % 2 == 0:
                even.append(i)
            else:
                odd.append(i)
        odd.sort()
        even.sort()
        res = 0
        for i in range(n):
            if arr[i] % 2 == 0:
                res = res*10 + even.pop()
            else:
                res = res*10 + odd.pop()
        return res