C++ Graeffe's square root method help

[klikaa]

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?

http://latex.codecogs.com/gif.latex?A_{k}=a_{k}^{2}+2\sum_{s=1}^{k}(-1)^{s}a_{k-s}*a_{k+s},&space;k=0,....n

 

cout<<"How many elements?"<<endl;
cin>>n;
cout<<"Insert x:"<<endl;
for(int i=0; i<n; i++)
{
cin>>elem;

}


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;

}

[Sensei]

C[j]=C[j]+(-1)^i*2*(elem[j-1]*elem[j+i]);

 

 

value ^ power is not working in C/C++ the way as in math.

 

It's bitwise xor operator..

 

http://en.wikipedia.org/wiki/Operators_in_C_and_C%2B%2B

Edited January 26, 2014 by Sensei

[Endy0816]

-snip

Edited January 26, 2014 by Endy0816

[klikaa]

thanks, that was the problem ))