from exp import Val, Add
def parse(s: str):
   num = int(s)
   return Val(num)
e = parse("123")
print(e)
s = "1+2"
pos = s.find('+')
print('pos',pos)
s1 = s[0:pos]
s2 = s[pos+1:]
print(s, s1, s2)
from exp import Val, Add
def parse(s: str):
   num = int(s)
   return Val(num)
e = parse("123")
print(e)
s = "1+2"
pos = s.find('+')
print('pos',pos)
s1 = s[0:pos]
s2 = s[pos+1:]
print(s, s1, s2)