#include <bits/stdc++.h>
using namespace std;
vector<int> graph[2000001];
int par[2000001], n = 0, type[2000001], sz[2000001], mn[2000001], mx[2000001];
void dfs(int i) {
if (graph[i].empty()) return;
int u = graph[i][0], v = graph[i][1];
dfs(u);
dfs(v);
sz[i] += sz[u] + sz[v];
if (type[i] == 1) {
mn[i] = min(mn[u], mn[v]);
mx[i] = mx[u] + mx[v] - 1;
} else if (type[i] == 2) {
mn[i] = mn[u] + mn[v];
mx[i] = max(sz[u] + mx[v], sz[v] + mx[u]);
}
}
int main() {
string s;
cin >> s;
int curr = 0;
for (int i = 0; i < s.size(); i++) {
if (s[i] == 'm') {
n++;
par[n] = curr;
graph[curr].push_back(n);
curr = n;
if (i + 2 < s.size() && s[i + 2] == 'n') {
type[curr] = 1;
} else {
type[curr] = 2;
}
i += 3;
}
else if (s[i] == '?') {
n++;
graph[curr].push_back(n);
curr = n;
mn[curr] = mx[curr] = sz[curr] = 1; }
else { curr = par[curr];}
}
dfs(1);
cout << mx[1] - mn[1] + 1;
return 0;
}
