package algs24;
import stdlib.*;
import java.util.Arrays;

public class FixedPQSortedDecreasing implements PQ {
  private int N;
  private double[] a;
  
  public FixedPQSortedDecreasing(int capacity){ N = 0; a = new double[capacity+1]; }  
  public void toGraphviz()          { }
  public String toString ()         { return Arrays.toString(a).replaceAll(" 0\\.0", " ").replaceAll("\\[0\\.0", "[ ").replaceAll("\\.0", ""); }
  public int size()                 { return N; }
  public boolean isEmpty()          { return N == 0; }
  
  public void insert(double x) {
    if (x == 0) throw new Error ("No zeroes allowed");
    if (N >= a.length-1) throw new Error("Overflow");
    N++;
    a[N] = x;
    for (int j = N; j > 1 && a[j] > a[j-1]; j--)
      exch2(j, j-1);
  }
  public double min() {
    return a[N];
  }
  public double delMin() {
    double result = a[N]; 
    a[N] = 0.0;
    N--;
    return result;
  }
  private void exch2(int i, int j) {
    double oldi = a[i];
    double oldj = a[j];
    if (TestPQ.SHOW_STEPS) { StdOut.format("  exch(%2.0f,%2.0f)> %s\n", oldi, oldj, this); toGraphviz(); }
    a[i] = oldj;
    a[j] = oldi;
  }
}