#include <bits/stdc++.h>
using namespace std;
#define sz(x) int(x.size())
const int MAX_N = 1e7;
string s;
int l[MAX_N], r[MAX_N];
struct Val {
int l, r, sz;
};
Val solve(int u) {
if (s[u] == '?') return {1, 1, 1};
Val left = solve(l[u]), right = solve(r[u]), curr;
curr.sz = left.sz + right.sz;
if (s[u] == 'n') {
curr.l = min(left.l, right.l);
curr.r = left.r + right.r - 1;
} else if (s[u] == 'x') {
curr.l = left.l + right.l;
curr.r = max(right.sz + left.r, left.sz + right.r);
} else assert(false);
return curr;
}
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;
for (int i = 0; i < sz(s); i++) {
if (s[i] == '?' || s[i] == 'n' || s[i] == 'x') {
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;
}
}
Val ans = solve(st.top());
cout << ans.r - ans.l + 1 << '\n';
return 0;
}
