#include <iostream>
#include <iomanip>
#include <fstream>
#include <math.h>

using namespace std;

void calculations(float alphaVal, string outputFileName);

int main(int argc, char const *argv[])
{
    // calculate part a
    calculations(0.5, "P4A.txt");
    calculations(0.8, "P4B.txt");
    calculations(0.9,  "P4C.txt");

}

void calculations(float alphaVal, string outputFileName)
{
    ofstream outputFile;
    outputFile.open(outputFileName.c_str());
    float alpha = alphaVal;
    outputFile << fixed << setprecision(4);
    float estimatedRTT = 1.50, sampleRTT = 0.0;
    float timeOut = 0.0;
    outputFile << "Iteration #\t\tSampleRTT\t\tEstimatedRTT\t\tTimeOut\n";
    for (int i = 1; i < 31; i++)
    {
        if((i % 6)==0)
        { 
            sampleRTT = 5.0;
        }
        else sampleRTT = 1.0;
        estimatedRTT = alpha * estimatedRTT + (1 - alpha) * sampleRTT;
        timeOut = 2 * estimatedRTT;
        outputFile << i << "\t\t\t\t" << setw(5) << setfill(' ') << sampleRTT << setw(10) << setfill(' ') 
        << "\t\t" << estimatedRTT << setw(16) << setfill(' ') <<  timeOut << endl;
    }
    
    outputFile.close();
}