@StefanPochmann said in Short simple C++:

for (int i=nums.size()-1, j=0, k=i/2+1; i>=0; i--)

nums[i] = sorted[i&1 ? k++ : j++];

I got it now. didn't find @StefanPochmann 's explain link earlier.

For some guys make the same mistake as mine, here's a head up.

Stefan's insert order makes the middle consecutive two same number M.

Large half M go way back to end but small half M go front. Very clever!

As a tip here to help anyone has the same problem as mine, go check Stefan's link up there.

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previous post below

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Hello, I take the same idea as yours instead of putting value from i==size-1, I start i from 0.

It got Wrong answer.

Input:

[4,5,5,6]

Output:

[4,5,5,6]

Expected:

[5,6,4,5]

Does it mean it better assigning value as your order from end to begin? And may I ask what make you choose this order? Thank you!

```
class Solution {
public:
void wiggleSort(vector<int>& nums) {
vector<int> sorted(nums);
sort(sorted.begin(), sorted.end());
//len=1 0
//1
//len=2 0(1)
//
//len=4 01(2)3
//
//len=5 012(3)4
//(len+1)/2=3
//len=6 012(3)45
//(len+1)/2=3
//len=7 0123(4)56
//len+1)/2=4
//[4,5,5,6]
/*
for (int i=nums.size()-1{3}, j=0, k=i/2+1{2}; i>=0; i--){
nums[i] = sorted[i&1 ? k++ : j++];
}*/
//[ [1]5 ,[3]6 ,[0]4, [2]5 ]
/*
for(int i=(nums.size()-1), j=0, k=(nums.size()+1)/2;i>=0;i--){
//cout<<(i&1)<<"j="<<j<<"k="<<k<<endl;
nums[i]= ((i&1)==0)? sorted[j++] : sorted[k++];
//cout<<(i&1)<<"j="<<j<<"k="<<k<<endl;
}*/
for(int i=0, j=0, k=(nums.size()+1)/2;i<nums.size();i++){
nums[i]= ((i&1)==0)? sorted[j++] : sorted[k++];
}
}
};
```