https://www.acmicpc.net/problem/1918 후위표기식으로 만들자. # -*- encoding: cp949 -*- s=raw_input() stack = [] answer = '' for c in s: if c.isalpha(): answer += c else: if len(stack)==0: stack.append(c) else: while stack: if stack[-1] in ['*','/'] and c not in ['(',')']: answer += stack.pop() elif stack[-1] in ['+','-'] and c in ['+','-']: answer += stack.pop() else: break if c!=')': stack.append(c) if c=..