The value for pi can be determined by the series equation

Write an interactive program that asks the user how many terms of the series equation to use in approximating

��. Then calculate and display the approximation. Test your program for 10, 20 and 30.

My output is wrong I suspect it is from the equation 'series'Code:#include <iostream> #include <cmath> using namespace std; int main () { double series, pi; int n, i; cout <<"Enter the number of terms: \n"; cin >>i; for (n=1; n<=i; n++) { series=((-1)^(n-1))/(2*n-1); pi=series+pi; cout<<n<<endl; cout<<pi<<endl; } cout <<"The pi in "<<i<<" terms is "<<pi*4 <<endl; system ("pause"); return 0; }

Thank you.