#include <iostream>
//#include <ifstream>
#include <string>
#include <fstream>
#include <sys/time.h>
#include <stdio.h>
#include <unistd.h>

using namespace std;

        int *a;
        
        int recursion(int* a, int num, int final, int sum)
        {
         if(num==final) return sum;
	 else {
          sum += a[num];
          cout<<sum << endl;  
          return recursion(a, num+1, final, sum);
	 }
        }

        int main (void)
        {
          int *a;
          int n=0;  // number of elements in the array a
          int sum=0; // we’ll use this for adding numbers
          ifstream babyfile;
          string thefile;

    struct timeval start, end;
    long mtime, seconds, useconds;//time constants


            //cout<<endl<<"What file would you like to read?"<<endl;
            //cin>>thefile;

          babyfile.open ("thefile.txt");
          if(babyfile.fail())
          {
            cout<<endl<<"Um sorry... Your file sucks!";
          }

          if (babyfile.is_open()){
            cout<<endl<<"Great news! Your file rocks!";
          }

        ifstream in("thefile.txt");
        std::string unused;
        while ( std::getline(in, unused) )
        ++n;
        
        //babyfile >> 
        cout<<endl<<"You have "<<n<<" numbers!"<<endl;
        
        a = new int [n];
   
   for (int m=0;m<n;m++)
    {
        babyfile >> a[m];
        //cout << a[m] << endl;
    }
  //Close the file stream
  in.close();
       

/* here goes code to read n numbers into a, probably from a file
        Make sure to allocate space to a
     */
     // the next part is the loop you are supposed to replace by recursion.
     //finding the sum of the whole thing.
     //sum = 0;
     gettimeofday(&start, NULL);
     for (int i = 0; i < n; i ++)
         sum += a[i];
  
     // This is the end of the loop.
     cout <<"Here is the sum: "<< sum << endl;
    gettimeofday(&end, NULL);
//find out what the time is
    seconds  = end.tv_sec  - start.tv_sec;
    useconds = end.tv_usec - start.tv_usec;

    mtime = ((seconds) * 1000000 + useconds) + 0.5;

    printf("Elapsed time for the for loop: %ld microseconds\n", mtime);
  
  gettimeofday(&start, NULL);   
     cout<<recursion(a,0,n,0);
  cout<<endl;
  gettimeofday(&end, NULL);

    seconds  = end.tv_sec  - start.tv_sec;
    useconds = end.tv_usec - start.tv_usec;

    mtime = ((seconds) * 1000000 + useconds) + 0.5;

    printf("Elapsed time for the recursive function: %ld microseconds\n", mtime);

       delete [] a;//dynamically deallocates memory huhrah!

return 0; }