def parse(s: str):
if s.rfind('+') > 0: #足し算
pos = s.rfind('+')
s1 = s[:pos]
s2 = s[pos + 1:]
return Add(parse(s1), parse(s2))
elif s.rfind('-') > 0: #引き算
pos = s.rfind('-')
s1 = s[:pos]
s2 = s[pos + 1:]
return Sub(parse(s1), parse(s2))
elif s.rfind('*') > 0: #かけ算
pos = s.rfind('*')
s1 = s[:pos]
s2 = s[pos + 1:]
return Mul(parse(s1), parse(s2))
elif s.rfind('/') > 0: #割り算
pos = s.rfind('/')
s1 = s[:pos]
s2 = s[pos + 1:]
return Div(parse(s1), parse(s2))
else:
num = int(s)
return Val(num)
def parse(s: str):
pos = s.rfind("+") # +文字の位置を見つける
if pos > 0:
s1 = s[0:pos]
s2 = s[pos+1:]
return Add(parse(s1), parse(s2))
pos = s.rfind("-") # -文字の位置を見つける
if pos > 0:
s1 = s[0:pos]
s2 = s[pos+1:]
return Sub(parse(s1), parse(s2))
pos = s.rfind("*") # *文字の位置を見つける
if pos > 0:
s1 = s[0:pos]
s2 = s[pos+1:]
return Mul(parse(s1), parse(s2))
pos = s.rfind("/") # /文字の位置を見つける
if pos > 0:
s1 = s[0:pos]
s2 = s[pos+1:]
return Div(parse(s1), parse(s2))
num = int(s)
return Val(num)
def parse(s: str):
if s.find('+') > 0:
pos = s.find('+')
s1 = s[0:pos]
s2 = s[pos+1:]
return Add(parse(s1),parse(s2))
if s.rfind('-') > 0:
pos = s.find('-')
s1 = s[0:pos]
s2 = s[pos+1:]
return Sub(parse(s1),parse(s2))
if s.find('*') > 0:
pos = s.find('*')
s1 = s[0:pos]
s2 = s[pos+1:]
return Mul(parse(s1),parse(s2))
if s.find('/') > 0:
pos = s.find('/')
s1 = s[0:pos]
s2 = s[pos+1:]
return Div(parse(s1),parse(s2))
return Val(int(s))
def parse(s: str):
if s.find('+') > 0:
pos = s.find('+')
s1 = s[0:pos]
s2 = s[pos + 1:]
num = Add(parse(s1), parse(s2))
return num
if s.find('-') > 0:
pos = s.find('-')
s1 = s[0:pos]
s2 = s[pos + 1:]
num = Sub(parse(s1), parse(s2))
return num
if s.find('*') > 0:
pos = s.find('*')
s1 = s[0:pos]
s2 = s[pos + 1:]
num = Mul(parse(s1), parse(s2))
return num
if s.find('/') > 0:
pos = s.find('/')
s1 = s[0:pos]
s2 = s[pos + 1:]
num = Div(parse(s1), parse(s2))
return num
return Val(int(s))
def parse(s: str):
if s.find('+') > 0:
pos = s.find('+')
s1 = s[0:pos]
s2 = s[pois + 1:]
return Mul(parse(s1), parse(s2))
if s.find('*') > 0:
pos = s.find('*')
s1 = s[0:pos]
s2 = s[pos + 1:]
return Mul(parse(s1), parse(s2))
return Val(int(s))
def parse(s: str):
if s.find('+') > 0:
pos = s.find('+')
s1 = s[0:pos]
s2 = s[pos + 1:]
return Div(parse(s1), parse(s2))
if s.find('/') > 0:
pos = s.rfind('/') #-,/を計算するときは、rfindで逆から求める
s1 = s[0:pos]
s2 = s[pos + 1:]
return Div(parse(s1), parse(s2))
return Val(int(s))
def parse(s: str):
if s.find("+") > 0:
pos = s.find("+")
s1 = s[0:pos]
s2 = s[pos + 1:]
return Add(parse(s1), parse(s2))
if s.rfind("-") > 0:
pos = s.rfind("-")
s1 = s[0:pos]
s2 = s[pos + 1:]
return Sub(parse(s1), parse(s2))
if s.find("*") > 0:
pos = s.find("*")
s1 = s[0:pos]
s2 = s[pos + 1:]
return Mul(parse(s1), parse(s2))
if s.rfind("/") > 0:
pos = s.rfind("/")
s1 = s[0:pos]
s2 = s[pos + 1:]
return Div(parse(s1), parse(s2))
return Val(int(s))
def parse(s: str):
num = int(s)
return Val(num)
from exp import Val, Add, Sub, Mul, Div
def parse(s: str):
if s find('+') > 0:
pos = s.find('+')
s1 = s[0:pos]
s2 = s[pos+1:]
return Add(parse(s1), parse(s2))
if s.find('*') > 0:
pos = s.find('*')
s1 = s[0:pos]
s2 = s[pos+1:]
return Mul(parse(s1), parse(s2))
return Val(int(s))
e = parse("1-2-3")
print(e, e.eval())
assert e.eval() == -4
