// build an array data structure
int[] a = new int[4];
a[0] = 21;
a[1] = 22;
a[3] = 24;
a[4] = 25;

// build an array data structure using an array literal
int[] a = {21, 22, 23, 24}; // array literal



// build a BTree using nested constructors
BTree btree = new BTree("apple", null, new BTree("a", new BTree("b"), null));

// or build a BTree by adding sub trees
BTree btree = new BTree("apple");
btree.addRightTree(new BTree("a"));
btree.getRightTree().addLeftTree(new BTree("b"));

// or build a BTree using a string from the binary tree language
BTree btree = BuildBTree.buildBTree( "( apple () ( a b () ) )" ); // "tree literal"