题解 | #四则运算#
四则运算
https://www.nowcoder.com/practice/9999764a61484d819056f807d2a91f1e
import math
def jjcc(s):
while '*' in s or '/' in s:
for i in s:
if i=='*':
tmp=float(s[s.index(i)-1])*float(s[s.index(i)+1])
s=s[:s.index(i)-1]+[tmp]+s[s.index(i)+2:]
break
elif i=='/':
tmp=float(s[s.index(i)-1])/float(s[s.index(i)+1])
s=s[:s.index(i)-1]+[tmp]+s[s.index(i)+2:]
break
while '+' in s or '-' in s:
for i in s:
if i=='+':
tmp=float(s[s.index(i)-1])+float(s[s.index(i)+1])
s=s[:s.index(i)-1]+[tmp]+s[s.index(i)+2:]
break
elif i=='-':
if s.index('-') !=0:
tmp=float(s[s.index(i)-1])-float(s[s.index(i)+1])
s=s[:s.index(i)-1]+[tmp]+s[s.index(i)+2:]
else:
s=[-1*s[1]]+s[2:]
break
return s
t=''.join([' '+i+' ' if not i.isnumeric() else i for i in input()])
t=t.split()
while '(' in t or '[' in t or '{' in t:
for i in t[::-1]:
if i=='(':
idx1=len(t)-1-t[::-1].index('(')
idx2 =idx1+1+t[idx1+1:].index(')')
tmp=jjcc(t[idx1+1:idx2])
t=t[:idx1]+tmp+t[idx2+1:]
elif i =='{':
idx1 = len(t) - 1 - t[::-1].index('{')
idx2 =idx1+1+t[idx1+1:].index('}')
tmp=jjcc(t[idx1+1:idx2])
t = t[:idx1] + tmp + t[idx2 + 1:]
elif i =='[':
idx1 = len(t) - 1 - t[::-1].index('[')
idx2 =idx1+1+t[idx1+1:].index(']')
tmp=jjcc(t[idx1+1:idx2])
t = t[:idx1] + tmp + t[idx2 + 1:]
print(round(jjcc(t)[0]))
