def test_pop(self):
s = ArrayStack()
s.push(1)
self.assertEqual(s.pop(), 1)
s.push(2)
s.push(3)
s.pop()
self.assertEqual(s.top(), 2)
def test_transfer():
S = ArrayStack()
S.push(3)
S.push(2)
S.push(1)
print(S)
T = ArrayStack()
transfer(S, T)
print(T)
def test_stack_clear():
S = ArrayStack()
S.push(3)
S.push(2)
S.push(1)
print(S)
stack_clear(S)
print(S)
def test_reverse_stack():
S = ArrayStack()
S.push(3)
S.push(2)
S.push(1)
print(S)
reverse_stack(S)
print(S)
def reverse_list(items):
s = ArrayStack()
for item in items:
s.push(item)
for i in range(len(items)):
items[i] = s.pop()
def stack_clear(s: ArrayStack) -> None:
if s.is_empty():
return
s.pop()
return stack_clear(s)
def test_three_stack():
R = ArrayStack()
R.push(1)
R.push(2)
R.push(3)
S = ArrayStack()
S.push(4)
S.push(5)
T = ArrayStack()
T.push(6)
T.push(7)
T.push(8)
T.push(9)
three_stack(R, S, T)
print("R:")
print(R)
print("S:")
print(S)
def three_stack(R: ArrayStack, S: ArrayStack, T: ArrayStack):
R_len = len(R)
while not S.is_empty():
R.push(S.pop())
while not T.is_empty():
R.push(T.pop())
while len(R) > R_len:
S.push(R.pop())
def transfer(S: ArrayStack, T: ArrayStack) -> None:
while not S.is_empty():
T.push(S.pop())
def reverse_stack(S: ArrayStack):
s1 = ArrayStack()
s2 = ArrayStack()
transfer(S, s1)
transfer(s1, s2)
transfer(s2, S)