import sys
from itertools import groupby


def input(): return sys.stdin.readline().rstrip('\n')


def main():
    s = input()
    xplus = +1
    if s.startswith('-') or s.startswith('+'):
        xplus = -1 if s.startswith('-') else +1
        s = s[1:]

    for sgn, yplus in [('+-', +1), ('--', -1), ('-+', +1), ('++', -1), ('-', +1), ('+', -1)]:
        k = s.split(sgn)
        if len(k) == 2:
            x, y = map(int, k)
            print(x * xplus + y * yplus)
            return


if __name__ == '__main__':
    main()