class IntSet2
{
// Set class, sets stored as unordered partly-filled arrays
// Has toString rather than print method

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

 public IntSet2()
 {
  array = new int[MAX];
 }

 public void delete(int n)
 {
  int i;
  for(i=0; i<count&&array[i]!=n; i++) {}
  if(i<count)
     {
      for(;i<count; i++)
         array[i]=array[i+1];
      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 String toString()
 {
  int i;
  String str="{";
  if(count>0)
     {
      str+=array[0];
      for(i=1;i<count;i++)
         str+=","+array[i];
     }
  return str+"}";
 }
}