#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define fi first
#define se second
#define mp make_pair
#define fastIO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
const int N = (int)2e6 + 10;
int typ[N];
vector<int> nex[N];
/*
0 - min
1 - max
2 - ?
*/
int cnt[N];
int lf[N];
int rf[N];
/*
void dfs0(int u){
cout << u << " -> ";
if(typ[u] == 0){
cout << "min (";
}
else if(typ[u] == 1){
cout << "max (";
}
else{
cout << " ? ";
}
for(auto x : nex[u]){
cout << x << " ";
}
cout << ")\n";
for(auto x : nex[u]){
dfs0(x);
}
}
*/
void calc(int u){
if(typ[u] == 2){
cnt[u] = 1;
lf[u]=1;
rf[u]=1;
}
else{
for(auto x : nex[u]){
calc(x);
cnt[u] += cnt[x];
}
if(typ[u] == 0){
lf[u]=min(lf[nex[u][0]], lf[nex[u][1]]);
rf[u]=rf[nex[u][0]]+rf[nex[u][1]]-1;
}
else{
rf[u]=cnt[u]-min(cnt[nex[u][0]]-rf[nex[u][0]], cnt[nex[u][1]]-rf[nex[u][1]]);
lf[u]=lf[nex[u][0]]+lf[nex[u][1]];
}
}
}
int main(){
fastIO;
string s;
cin >> s;
if(s.size() == 1){
cout << "1\n";
return 0;
}
int id = 0;
vector<int> stek;
int cur;
int las = -1;
for(char x : s){
if(x == '('){
cur = id;
id ++ ;
if(!stek.empty()){
nex[stek.back()].push_back(cur);
}
typ[cur] = las;
stek.push_back(cur);
}
else if(x == ')'){
stek.pop_back();
}
else if(x == '?'){
cur = id;
id ++ ;
typ[cur] = 2;
nex[stek.back()].push_back(cur);
}
else{
if('a' <= x && x <= 'z'){
if(x == 'i'){
las = 0;
}
else if(x == 'x'){
las = 1;
}
else{
continue;
}
}
}
}
calc(0);
cout << rf[0]-lf[0]+1 << "\n";
return 0;
}
