class IntSet1
{
// Set class, sets stored as unordered partly-filled arrays

 private int[] array;
 private int count;
 final static int MAX=100;

 public IntSet1()
 {
  array = new int[MAX];
 }

 public void delete(int n)
 {
  int i;
  for(i=0; i<count&&array[i]!=n; i++) {}
  if(i<count)
     {
      count--;
      array[i]=array[count];
     }
 }

 public void add(int n)
 {
  int i;
  for(i=0; i<count&&array[i]!=n; i++) {}
  if(i==count)
     {
      array[count]=n;
      count++;
     }
 }

 public boolean member(int n)
 {
  int i;
  for(i=0; i<count&&array[i]!=n; i++) {}
  return i<count;
 }

 public void print()
 {
  int i;
  System.out.print("{");
  if(count>0)
     {
      System.out.print(array[0]);
      for(i=1;i<count;i++)
         System.out.print(","+array[i]);
     }
  System.out.println("}");
 }
}