15725번: 다항함수의 미분 ↗

import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta

BLANK = " "

inp = input
# inp = lambda : sys.stdin.readline()[:-1].strip()
mii = lambda x = BLANK : [*map(int,inp().split(x))]
mfi = lambda x = BLANK : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print


def solve():
  s = input()
  
  if 'x' not in s:
    p(0)
    return
  
  k = s.index('x')

  num = s[:k]
  
  if num == "-":
    p(-1)
  elif num == "":
    p(1)
  else:
    p(int(num))
  
  
if __name__ == "__main__":
  tc = 1

  for t in range(1, tc+1):
    ret = solve()