An important task when processing arithmetic expressions is to mach delimiters.
We can use Stack to solve this problem.
def is_matched(expr):
left=‘({[‘
right=‘)}]‘
S=ArrayStack()
for c in expr:
if c in left:
S.push(c)
elif c in right:
if S.is_empty():
return False
if right.index(c)!=left.index(S.pop()):
return False
return S.is_empty()
[Data Structure] An Algorithm for Matching Delimiters
原文：https://www.cnblogs.com/chiyeung/p/9661445.html