Pi Approximation

conorhogan.cpp

// http://min.us/mvk51zd
#include <iostream>
#include <cmath>
#include <iomanip>
#include <cstdlib>

using namespace std;

double machin(void) {
    long double pi_approx = 0.0L, t;
    for(int k=0; k<10; ++k) {
        t = 1.0L + 2.0L*k;
        pi_approx += -(pow(-1.0L,k)*pow(1195.0L,-t)*(pow(5.0L,t)-4.0*pow(239.0L,t)))/t;
        cout << setprecision(12) << "Iteration " << k << ":  " << 4.0L*pi_approx << endl;
    }
    return 4.0*pi_approx;
}

int main(int argc, char *argv[]) {
    cout << "Final Approximation: " << setprecision(12) << machin() << endl;
    return EXIT_SUCCESS;
}