def main():
s = Stack()
print(len(s))
s.push(1)
print(s.top())
print(s.is_empty())
print(s.pop())
print(s.is_empty())
try:
print(s.pop())
except IndexError:
print('Error')
try:
print(s.top())
except IndexError:
print('Error')
s.push(1)
s.push(2)
s.push(3)
print(len(s))
print(s.pop())
print(s.pop())
print(s.pop())
print(s.is_empty())
def matcher(line):
left = "({["
right = "]})"
square = "[]"
curl = "{}"
roun = "()"
s = Stack()
for char in line:
try:
if char in left:
s.push(char)
elif char in right and s.top() in square and char in square:
s.pop()
elif char in right and s.top() in curl and char in curl:
s.pop()
elif char in right and s.top() in roun and char in roun:
s.pop()
except IndexError:
return False
return s.is_empty()
def matcher(line):
s = Stack()
for char in line:
if char == "(" or char == "{" or char == "[":
s.push(char)
elif char == ")" or char == "}" or char == "]":
try:
if not s.is_empty:
return False
elif char == ")" and s.top() == "(":
s.pop()
elif char == "}" and s.top() == "{":
s.pop()
elif char == "]" and s.top() == "[":
s.pop()
else:
return False
except:
return False
return s.is_empty()
def calculator(l):
s = Stack()
for i in l.split():
if i in binops.keys():
y = s.pop()
x = s.pop()
s.push(binops[i](x, y))
elif i in uniops.keys():
s.push(uniops[i](s.pop()))
else:
s.push(float(i))
return s.top()
def calculator(line):
stack = Stack()
for e in line.split():
if e in binops.keys():
y = stack.pop()
x = stack.pop()
stack.push(binops[e](x, y))
elif e in uniops.keys():
stack.push(uniops[e](stack.pop()))
else:
stack.push(float(e))
return stack.top()
def matcher(s):
stack = Stack()
for e in s:
if e in lefties:
stack.push(e)
try:
if e in righties and stack.top() == mapping[e]:
stack.pop()
except IndexError:
return False
if stack.is_empty():
return True
return False
def matcher(l):
s = Stack()
for c in l:
if c in lefties:
s.push(c)
try:
if c in righties and s.top() == dictr[c]:
s.pop()
except IndexError:
return False
if s.is_empty():
return True
return False
def calculator(line):
chars = line.split()
s = Stack()
for c in chars:
if is_num(c):
s.push(float(c))
elif c in un:
s.push(float(uniops[c](s.pop())))
elif c in binops:
b = s.pop()
s.push(float(binops[c](s.pop(), b)))
return s.top()
def calculator(line):
s = Stack()
normalop = ["+", "-", "*", "/"]
specialop = ["r", "n"]
l = line.split()
for char in l:
if char not in normalop and char not in specialop:
s.push(char)
elif char in normalop:
p1 = float(s.pop())
p2 = float(s.pop())
s.push(normal(char, p1, p2))
elif char in specialop:
p = float(s.pop())
s.push(special(char, p))
return float(s.top())
def matcher(line):
d = {')': '(', '}': '{', ']': '['}
s = Stack()
for c in line:
if c in d.values():
s.push(c)
elif c in d.keys():
if s.is_empty():
return False
if s.top() != d[c]:
return False
s.pop()
return s.is_empty()
def matcher(line):
s = Stack()
left = '({['
right = ')}]'
brackets = ['()', '{}', '[]']
line = line.strip()
try:
for ch in line:
if ch in left:
s.push(ch)
else:
if s.top() + ch in brackets:
s.pop()
return s.is_empty()
except:
return False
def matcher(line):
s = Stack()
lefties = '({['
righties = ')}]'
brackets = ['()', '{}', '[]']
line = line.strip()
try:
for pattern in line:
if pattern in lefties:
s.push(pattern)
else:
if s.top() + pattern in brackets:
s.pop()
return s.is_empty()
except:
return False
def calculator(line):
def plus(a, b):
return a + b
def subtract(a, b):
return a - b
def product(a, b):
return a * b
def divide(a, b):
return a / b
def remainder(a, b):
return a % b
def power(a, b):
return a**b
def neg(a):
return -a
def square(a):
return a**2
def sqrt(a):
return math.sqrt(a)
def log(a):
return math.log(a)
binops = {
'+': plus,
'-': subtract,
'*': product,
'/': divide,
'%': remainder,
'**': power,
}
uniops = {
'n': neg,
's': square,
'r': sqrt,
'l': log,
}
s = Stack()
for n in line.split():
if n.replace('.', '').isdigit():
s.push(float(n))
elif n in binops:
b = s.pop()
a = s.pop()
c = float(binops[n](a, b))
s.push(c)
elif n in uniops:
a = s.pop()
b = uniops[n](a)
s.push(b)
return s.top()