class Stack():

def __init__(self):

self.vec = []

def push(self, item):

self.vec.append(item)

def pop(self):

self.vec.pop()

def top(self):

return self.vec[len(self.vec) - 1]

def is_empty(self):

return self.vec == []

def size(self):

return len(self.vec)

'''

#convert num to different base

def convert1(stk, num, base):

digit = ['0', '1', '2', '3', '4', '5', '6', '7',

'8', '9', 'A', 'B', 'C', 'D', 'E', 'F']

if num > 0:

stk.push(digit[num % base])

convert(stk, num // base, base)

def convert2(stk, num, base):

digit = ['0', '1', '2', '3', '4', '5', '6', '7',

'8', '9', 'A', 'B', 'C', 'D', 'E', 'F']

while num > 0:

stk.push(digit[num % base])

num = num // base

s = Stack()

n= []

convert2(s, 12345, 8)

while s.is_empty() == False:

n.append(s.top())

s.pop()

print(n)

'''

#stack permutation

def permutationstacks(stk1, stk2):

tmp1 = Stack()

tmp2 = Stack()

while stk2.is_empty() == False:

tmp2.push(stk2.top())

stk2.pop()

while stk1.is_empty() == False or (tmp1.is_empty() == False and tmp1.top() == tmp2.top()):

if tmp1.is_empty() == False and tmp1.top() == tmp2.top():

stk2.push(tmp1.top())

tmp1.pop()

tmp2.pop()

else:

tmp1.push(stk1.top())

stk1.pop()

# print(stk1.vec)

# print(tmp1.vec)

# print(tmp2.vec)

# print('\n')

if stk1.is_empty() == True and tmp1.is_empty() == True:

return True

return False

def permutationstk():

s = Stack()

s.vec = [4, 3, 2, 1]

s1 = Stack()

s1.vec = [3, 2, 4, 1]

s2 = Stack()

s2.vec = [1, 2, 3, 4]

print(permutationstacks(s, s1))

print(permutationstacks(s, s2))

'''

s = Stack()

print(s.is_empty())

s.push(4)

s.push('dog')

print(s.top())

print(s.size())

s.pop()

s.top()

print(s.size())

'''

if __name__ == '__main__':

permutationstk()