It seems that test cases don't contain cases with negative integers. Not considering negative integers, we have below solution.

We can also write radix-sort considering negative integers, just a little complicated.

```
class Solution(object):
def radixSort(self, nums):
nums = map(str, nums)
k = max(map(len, nums))
nums = ['0' * (k - len(num)) + num for num in nums]
for i in xrange(k - 1, -1, -1):
buckets = [[] for _ in xrange(10)]
for num in nums:
buckets[ord(num[i]) - 48].append(num)
nums = sum(buckets, [])
return map(int, nums)
def wiggleSort(self, nums):
sortNums, n = self.radixSort(nums), len(nums) | 1
for i, num in enumerate(sortNums[::-1]):
nums[(2*i + 1) % n] = num
```