print 'Input:',
print ', '.join(str(x) for x in values)
print '\nPrefixed.:',
for node in tree.course_prefixed():
print node.data,
print
print '\nInfixed..:',
for node in tree.course_infixed():
print node.data,
print
print '\nPostfixed:',
for node in tree.course_postfixed():
print node.data,
print
print '\nSearch:',
print ', '.join(str(x) for x in values)
for x in values:
result = tree.search(x)
if result:
print result.data,
else:
print None,
result = None
