LC 0150 [M] Evaluate Reverse Polish Notation - ALawliet/algorithms GitHub Wiki
class Solution:
def evalRPN(self, tokens: List[str]) -> int:
stack = []
for x in tokens:
if x not in '+-*/': # isnumeric() doesn't work for neg numbers (-x)
stack.append(int(x))
else:
op = x
b = stack.pop()
a = stack.pop()
if op == '+':
stack.append(a+b)
elif op == '-':
stack.append(a-b)
elif op == '*':
stack.append(a*b)
elif op == '/':
stack.append(int(a/b))
return stack.pop()