#include <iostream>
#include <complex>
#include <iomanip>
#include <vector>
#include <algorithm>
#include <functional>
#include <bitset>
#include <queue>
#include <map>
#include <stack>
#include <cmath>
#include <cstdint>
using namespace std;
#define endl '\n'
#define db double
#define ll __int128
#define int long long
#define pb push_back
#define fs first
#define sd second
#define Mod long(1e9 + 7)
#define all(x) x.begin(), x.end()
#define unvisited long(-1)
#define Eps double(1e-9)
#define _for(i, n) for(int i = 0; i < (n); i++)
#define dbg(x) cout << #x ": " << x << endl;
const int Max = 1e6 + 7, Inf = 1e9 + 7;
void print(bool x) { cout << (x ? "YES" : "NO") << endl; }
string tostring (__int128 x)
{
string ans = "";
while(x > 0)
{
ans += (x % 10 + '0');
x /= 10;
}
reverse(all(ans));
return ans;
}
vector <vector<int>> v;
vector <int> a; int n;
pair <int, int> dfs(int node, int parent)
{
vector <pair<int, int>> s;
for(auto& u : v[node]) if(u != parent) {
s.push_back(dfs(u, node));
}
while (s.size() < 2){
s.push_back({ 0, 0 });
}
pair <int, int> ans = s.back();
s.pop_back();
for(auto& u : s){
if(a[node] == 0){
ans.fs = min(u.fs, ans.fs);
ans.sd = u.sd + ans.sd;
}
else{
ans.fs = u.fs + ans.fs;
ans.sd = min(u.sd, ans.sd);
}
}
if(a[node] == 0) ans.sd ++;
else ans.fs ++;
//cerr << node << " " << a[node] << " " << parent << " " << ans.fs << " " << ans.sd << endl;
return ans;
}
void solve()
{
string s; cin >> s;
vector <int> p; int node = 0; n = 0;
v.push_back(vector<int> ());
p.push_back(-1);
a.push_back(0);
for(int i = 0; i < (int) s.size(); i++)
{
n += (s[i] == '?');
if(s[i] == 'm'){
if(node != 0) {
v[node].push_back(v.size());
}
a.push_back((s[i+1] == 'a'));
p.push_back(node);
node = v.size();
v.push_back(vector<int> ());
}
if(s[i] == ')'){
node = p[node];
}
}
// cerr << n << endl;
pair <int, int> ans = dfs(1, 0);
cout << ((n - ans.sd) - ans.fs) << endl;
}
int32_t main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int Q = 1; //cin >> Q;
while (Q--)
{
solve();
}
return 0;
}
