//Use this file as a basis for your experiments
import java.io.FileNotFoundException;
import java.io.PrintWriter;

/**
 * Example timing analysis for linear search
 */
public class Timing {
  /**
   * Timing function for LinkedList add to end
   * @param n Size of experiment
   * @param k Number of times to repeat experiment
   * @return Seconds taken for experiment
   */
  public static double TimeFunction(int n, int k) {

    // Optional initialization before timing
    int[] arr = new int[n];
    for(int i = 0; i < n; ++i)
      arr[i] = (int)(Math.random() * Integer.MAX_VALUE);

    // Timing - repeat the experiment k times
    long start = System.nanoTime();

    for(int i = 0; i < k; ++i) {
      // Example function of linear search
      int key = -1;
      for(int x : arr)
        if(x == key)
          System.out.print("Error");
    }

    long stop = System.nanoTime();

    // Compute average from elapsed time
    double sec = (stop - start)/(double)1e9/k;
    return sec;
  }

  /**
   * Run all timing functions and output to terminal and csv file
   * @param args Command-line arguments. Ignored here.
   * @exception FileNotFoundException If system cannot open filename, exception.
   */
  public static void main(String[] args) throws FileNotFoundException {
    // Output devised to go to terminal/console AND csv (excel) file
    PrintWriter pw = new PrintWriter("data.csv");

    // Output title row
    System.out.printf("%10s %15s", "N", "Time");
    pw.print("N,Time");

    int N = 20000;                // Upper limit of input size to the experiment
    for(int n = 2; n < N; n*=2) { // Use powers of 2 only

      // Start a new row
      System.out.println();
      pw.println();

      // Output size column
      System.out.printf("%10s ", n);
      pw.print(n);
      int repeats = Math.max(10, N/n);

      // Output data cell for second column
      double tall = TimeFunction(n, repeats);
      System.out.printf("%15e", tall);
      pw.print("," + tall);
    }

    System.out.println();
    // Always flush and close!
    pw.flush();
    pw.close();
  }
}