import re
s=input()
s=re.sub(r'S','0',s)
s=re.sub(r'ing','1',s)
s=re.sub(r'[a-zA-Z]','',s)
l=list(map(int,list(s)))
c=0
for i in range(len(l)):
	if l[i]<1: c+=sum(l[i+1:])
print(c)