#---------------------------------------------------------------------
# Recursice computation of list length:
def rec_list_len(lis):
if not lis:
return 0
#print "calling rec_list_len with lis = {}".format(lis)
return 1 + rec_list_len(lis[1:])
print "Recursive computation of list length:"
print
for lis_siz in range(5):
lis = range(lis_siz)
lis_len = rec_list_len(lis)
print 'List: {} Length: {}'.format(lis, lis_len)
print
# Also test rec_list_len on other kinds of sequences than lists:
s = 'hello there'
print 'String: "{}" Length: {}'.format(s, rec_list_len(s))
print
s = 'the quick brown fox'
print 'String: "{}" Length: {}'.format(s, rec_list_len(s))
print
student = ('Jack', 25, 'New York')
print 'Tuple: {} Length: {}'.format(student, rec_list_len(student))
print
student = ('Jill', 27, 'Paris', 'France')
print 'Tuple: {} Length: {}'.format(student, rec_list_len(student))
print
#---------------------------------------------------------------------
# Recursive list sum computation.
# Assumes list items are numbers.
def rec_list_sum(lis):
if not lis:
return 0
return lis[0] + rec_list_sum(lis[1:])
for r in range(5):
lis = range(r)
print "Sum:", rec_list_sum(lis), "List:", lis
#---------------------------------------------------------------------
# Recursive list product computation.
# Assumes list items are numbers.
def rec_list_product(lis):
if not lis:
return 1
return lis[0] * rec_list_product(lis[1:])
for r in range(1, 7):
lis = range(1, r)
print "Product:", rec_list_product(lis), "List:", lis
#---------------------------------------------------------------------
