So i have to write a c++ program for the Graeffe's square root method

I have am stuck here when i have this formula transform into c++ code, the formula is on the link

The code works particulary, the (elem[j-1]*elem[j+i]) doesn't work, it's beeing ignored and i don't know why... can any one help me?

```
cout<<"How many elements?"<<endl;
cin>>n;
cout<<"Insert the elements:"<<endl;
for(int i=0; i<n; i++)
{
cin>>elem[i];
}
C[0]=pow(elem[0],2);
for(int j=1; j<n; j++)
{
C[j]=pow(elem[j],2);
int i=1;
while((i+j)<=n-1&&(i<=j))
{
C[j]=C[j]+(-1)^i*2*(elem[j-1]*elem[j+i]);
i=i+1;
}
cout<<"C"<<j<<":"<<C[j]<<endl;
}
```