package algs21;
import stdlib.*;
/* ***********************************************************************
 *  Compilation:  javac ZSelectionBars.java
 *  Execution:    java ZSelectionBars N
 *  Dependencies: StdDraw.java
 *
 *  Selection sort N random real numbers between 0 and 1, visualizing
 *  the results by ploting bars with heights proportional to the values.
 *
 *  % java ZSelectionBars 20
 *
 *************************************************************************/

public class XBarsSelection {

  public static void sort(double[] a) {
    int N = a.length;
    for (int i = 0; i < N; i++) {
      int min = i;
      for (int j = i+1; j < N; j++)
        if (less(a[j], a[min])) min = j;
      show(a, i, min);
      exch(a, i, min);
    }
  }

  private static void show(double[] a, int i, int min) {
    StdDraw.setYscale(-a.length + i + 1, i);
    StdDraw.setPenColor(StdDraw.LIGHT_GRAY);
    for (int k = 0; k < i; k++)
      StdDraw.line(k, 0, k, a[k]*.6);
    StdDraw.setPenColor(StdDraw.BLACK);
    for (int k = i; k < a.length; k++)
      StdDraw.line(k, 0, k, a[k]*.6);
    StdDraw.setPenColor(StdDraw.BOOK_RED);
    StdDraw.line(min, 0, min, a[min]*.6);
  }

  private static boolean less(double v, double w) {
    return v < w;
  }

  private static void exch(double[] a, int i, int j) {
    double t = a[i]; a[i] = a[j]; a[j] = t;
  }

  public static void main(String[] args) {
    args = new String[] { "10" };
    int N = Integer.parseInt(args[0]);
    StdDraw.setCanvasSize(N*8, N*32);
    StdDraw.setXscale(-1, N+1);
    StdDraw.setPenRadius(.006);
    sort (ArrayGenerator.doubleRandomUnique (N));
    //sort (ArrayGenerator.partiallySortedUnique (N));
    //sort (ArrayGenerator.sortedUnique (N));
    //sort (ArrayGenerator.reverseSortedUnique (N));
  }

}