#include <bits/stdc++.h>
using namespace std;
#define sz(x) int(x.size())
#define all(x) begin(x),end(x)
#define forsn(i,s,n) for(int i=int(s);i<int(n);i++)
#define forn(i,n) for(int i=0;i<int(n);i++)
#define dforsn(i,s,n) for(int i=int(n)-1;i>=int(s);i--)
#define dforn(i,n) for(int i=int(n)-1;i>=0;i--)
#define dbg(x) cerr<<#x<<": "<<x<<endl
#define pb push_back
typedef vector<int> vi;
typedef pair<int, int> ii;
const int MAXN=1e6+20;
string s;
int l[MAXN],r[MAXN];
struct Val{
int l,r,sz;
int cant(){return r-l+1;}
};
Val solve(int u){
if(s[u]=='?') return {1,1,1};
Val lch=solve(l[u]);
Val rch=solve(r[u]);
Val res;
res.sz=lch.sz+rch.sz;
if(s[u]=='n'){//min
res.l=min(lch.l,rch.l);
res.r=lch.r+rch.r-1;
}else if(s[u]=='x'){//max
res.l=lch.l+rch.l;
res.r=max(rch.sz+lch.r,lch.sz+rch.r);
}else assert(false);
return res;
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> s;
memset(l, -1, sizeof l);
memset(r, -1, sizeof r);
stack<int> st;
forn(i,sz(s)){
if(s[i]=='n'||s[i]== 'x'||s[i]=='?'){
st.push(i);
}else if(s[i]==','||s[i]==')'){
int j=st.top(); st.pop();
if (l[st.top()] == -1) l[st.top()] = j;
else r[st.top()] = j;
}
}
cout<<solve(st.top()).cant()<<'\n';
return 0;
}
