inp = input()

flip = 0

while True:
  i = inp.find('++')
  j = inp.find('--')
  if i == -1 or j == -1:
    break
  i += 1
  j += 1
  
  if i > j:
    i, j = j, i
 
  inp = inp[:i] + inp[i:j][::-1] + inp[j:]
  flip += 1

print(flip)