[LeetCode] Wiggle Sort

Wiggle Sort

Given an unsorted array

nums

, reorder it in-place such that

nums[0] <= nums[1] >= nums[2] <= nums[3]...

.

For example, given

nums = [3, 5, 2, 1, 6, 4]

, one possible answer is

[1, 6, 2, 5, 3, 4]

.

贪心，数学归纳法很容易证明出来。

class Solution {
public:
void wiggleSort(vector<int>& nums) {
int flag = 1;
for (int i = 1; i < nums.size(); ++i) {
if (nums[i] * flag < nums[i-1] * flag)
swap(nums[i], nums[i-1]);
flag = -flag;
}
}
};