added example 2.8_17

2.8_17.pl

+% nacteni:
+/* ['2.8_17.pl']. */
+
+add(T,X,T1) :- addroot(T,X,T1).
+add(t(L,Y,R),X,t(L1,Y,R)) :- gt(Y,X),add(L,X,L1).
+add(t(L,Y,R),X,t(L,Y,R1)) :- gt(X,Y),add(R,X,R1).
+
+addroot(nil ,X,t( nil ,X, nil )).
+addroot(t(L,Y,R),X,t(L1,X,t(L2,Y,R))) :- gt(Y,X),addroot(L,X,t(L1,X,L2)).
+addroot(t(L,Y,R),X,t( t(L,Y,R1),X,R2)) :- gt(X,Y),addroot(R,X,t(R1,X,R2)).
+addroot(t(L,X,R),X,t(L,X,R)).
+
+del(T,X,T1) :- add(T1,X,T).
+
+gt(X, Y) :- X > Y.
+
+show(T) :- show2(T,0).
+show2(nil,_).
+show2(t(L,X,R),Indent) :- Ind2 is Indent+2,show2(R,Ind2),tab(Indent),
+                          write(X),nl,show2(L,Ind2).
+
+%maketree(+LIST,-TREE)
+%LIST - prvky kt. maji byt ve stromu ulozeny
+%TREE - vytvoreny strom
+%note: vypise vytvoreny strom!!!
+maketree([],nil).
+maketree([H|T],TREE) :- maketreeacc([H|T],nil,TREE), show(TREE).
+%akumulatorova verze predikatu =>
+%optimalizace pro "odstraneni" backtrackingu a zrychleni
+maketreeacc([],TREE,TREE).
+maketreeacc([H|T],PTREE,TREE) :- add(PTREE,H,RTREE), 
+                                maketreeacc(T,RTREE,TREE).
+
+%delitems(+TREE,+ITEMS,-NEWTREE).
+%smaze ze stromu TREE uzly odpovidajici polozkam ITEMS, vrati NEWTREE
+%(pokud takove neexistuji, pokracuje-pro zmenu chovani odebrat posledni kl.)
+%note: vypise vytvoreny strom!!!
+delitems(TREE,[],TREE) :- show(TREE).
+delitems(TREE,[H|T],NEWTREE) :- del(TREE,H,PTREE), 
+                                delitems(PTREE,T,NEWTREE).
+%v pripade, ze dany prvek ve stromu neni, pokracuj...
+delitems(TREE,[_H|T],NEWTREE) :- delitems(TREE,T,NEWTREE). 
+
+
+% demonstracni vypis
+
+  % abychom se vyhli varovanim "Redefined static procedure ..."
+:- dynamic
+       start/0.
+       
+start:- 
+    write('Binarni stromy'),nl,
+    write('--------------'),nl, nl,
+    write('Vytvoreni stromu: '),nl,
+    write('add(nil ,6,Tr),add(Tr,8,Tr1), add(Tr1,2,Tr2),'),nl, 
+    write('add(Tr2,4,Tr3), add(Tr3,1,Tr4), show(Tr4) :'),nl,
+    add(nil ,6,Tr),add(Tr,8,Tr1), add(Tr1,2,Tr2), add(Tr2,4,Tr3), add(Tr3,1,Tr4),
+    show(Tr4),
+
+    write('Smazani uzlu s hodnotou 8:'),nl,
+    write('del(Tr4, 8, Tr5), show(Tr5) :'),nl,
+    del(Tr4, 8, Tr5), show(Tr5),
+
+    write('Smazani uzlu s hodnotou 2:'),nl,
+    write('del(Tr5, 2, Tr6), show(Tr6) :'),nl,
+    del(Tr5, 2, Tr6), show(Tr6).
+
+?-start.
+
+:- retractall(write_all_X/3).
+:- retractall(start/0).

2.8_17.py

+#!/usr/bin/env python
+# encoding=utf-8 (pep 0263)
+
+nil = None
+
+def add(tree, x):
+    yield addroot(tree, x)
+    if tree == nil:
+        return
+    left, y, right = tree
+    if y > x:
+        yield (add(left, x), y, right)
+    else:
+        yield (left, y, add(right, x))
+
+def addroot(tree, x):
+    if tree == nil:
+        return (nil, x, nil)
+    left, y, right = tree
+    if y > x:
+        left1, _, left2 = addroot(left, x)
+        return (left1, x, (left2, y, right))
+    if y < x:
+        right1, _, right2 = addroot(right, x)
+        return ((left, y, right1), x, right2)
+    return tree
+
+def del_(tree, x):
+    if tree == nil:
+        return
+    for tree1 in delroot(tree, x):
+        yield tree1
+    left, y, right = tree
+    if y > x:
+        for left1 in del_(left, x):
+            yield (left1, y, right)
+    else:
+        for right1 in del_(right, x):
+            yield (left, y, right1)
+
+def delroot(tree, x):
+    if tree == nil:
+        return
+    tree_left, tree_y, tree_right = tree
+    if tree_y != x:
+        return
+    if tree_left == nil and tree_right == nil:
+        yield nil
+    if tree_right != nil:
+        left1 = tree_left
+        left2, y, right = tree_right
+        if y > x:
+            for left in delroot((left1, x, left2), x):
+                yield (left, y, right)
+    if tree_left != nil:
+        left, y, right1 = tree_left
+        right2 = tree_right
+        if y < x:
+            for right in delroot((right1, x, right2), x):
+                yield (left, y, right)
+    yield tree
+
+def show(tree):
+    show2(tree, 0)
+
+def show2(tree, indent):
+    if tree == nil:
+        return
+    left, root, right = tree
+    show2(right, indent+2)
+    print("%s%s" % (" " * indent, root))
+    show2(left, indent+2)
+
+# demonstracni vypis
+if __name__ == "__main__":
+    print("Binarni stromy")
+    print("--------------\n")
+    print("Vytvoreni stromu:")
+    print("T = next(add(nil, 6)); T1 = next(add(T, 8)); T2 = next(add(T1, 2)); " +
+          "T3 = next(add(T2, 4)); T4 = next(add(T3, 1)); show(T4) :")
+    T = next(add(nil, 6))
+    T1 = next(add(T, 8))
+    T2 = next(add(T1, 2))
+    T3 = next(add(T2, 4))
+    T4 = next(add(T3, 1))
+    show(T4)
+
+    print("\nSmazani uzlu s hodnotou 8:")
+    print("T5 = next(del_(T4, 8)); show(T5) :")
+    T5 = next(del_(T4, 8))
+    show(T5)
+
+    print("\nSmazani uzlu s hodnotou 2:")
+    print("T6 = next(del_(T5, 2)); show(T6) :")
+    T6 = next(del_(T5, 2))
+    show(T6)

2.8_17.py.out

+Binarni stromy
+--------------
+
+Vytvoreni stromu:
+T = next(add(nil, 6)); T1 = next(add(T, 8)); T2 = next(add(T1, 2)); T3 = next(add(T2, 4)); T4 = next(add(T3, 1)); show(T4) :
+    8
+      6
+  4
+    2
+1
+
+Smazani uzlu s hodnotou 8:
+T5 = next(del_(T4, 8)); show(T5) :
+    6
+  4
+    2
+1
+
+Smazani uzlu s hodnotou 2:
+T6 = next(del_(T5, 2)); show(T6) :
+    6
+  4
+1