#include <bits/stdc++.h>
#define ll long long
using namespace std;
ll ans=1;
void Solve(string s)
{
ll t=0;
if (s[1]=='a')
t=1;
string arg0="",arg1="";
ll pos=4,cnt=0;
while (pos<s.size())
{
if (s[pos]=='(')
cnt++;
else if (s[pos]==')')
cnt--;
if (!cnt && s[pos]==',')
{
pos++;
break;
}
arg0+=s[pos++];
}
while (pos<s.size()-1)
arg1+=s[pos++];
ll t0=0,t1=0;
if (arg0.size()!=1 && arg0[1]=='a')
t0=1;
if (arg1.size()!=1 && arg1[1]=='a')
t1=1;
if (arg0.size()==1 && arg1.size()==1)
return;
if (arg0.size()!=1 && arg1.size()==1)
{
ans+=(t0!=t);
Solve(arg0);
return;
}
if (arg0.size()==1 && arg1.size()!=1)
{
ans+=(t1!=t);
Solve(arg1);
return;
}
if (t0!=t || t1!=t)
ans++;
Solve(arg0);
Solve(arg1);
}
int main()
{
ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
string s;
cin >> s;
Solve(s);
cout << ans;
return 0;
}
