5. Consider the following grammar: btree : NIL | LPAREN btree COMMA value COMMA btree RPAREN value : digit | digit value digit : 01|2|3|4|5|6|7| 8 | 9 Some examples of binary trees are: (NIL,12,NIL) ((NIL, 12, NIL), 20, (NIL,15,NIL)) ((NIL,3,NIL),8, ((NIL,12,NIL),20, (NIL,15,NIL))) Augment this grammar with attributes and the attribute computation functions and predicates to accept binary trees that are "balanced". A balanced binary tree is one in which the heights of the subtrees at each interior node are within one of each other. 5. Consider the following grammar: btree : NIL | LPAREN btree COMMA value COMMA btree RPAREN value : digit | digit value digit : 01|2|3|4|5|6|7| 8 | 9 Some examples of binary trees are: (NIL,12,NIL) ((NIL, 12, NIL), 20, (NIL,15,NIL)) ((NIL,3,NIL),8, ((NIL,12,NIL),20, (NIL,15,NIL))) Augment this grammar with attributes and the attribute computation functions and predicates to accept binary trees that are "balanced". A balanced binary tree is one in which the heights of the subtrees at each interior node are within one of each other