#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
#include <unordered_map>
#include <unordered_set>
#include <cassert>
using namespace std;
typedef long long ll;
#define ss second
#define ff first
#define all(X) X.begin(), X.end()
#define rall(X) X.rbegin(), X.rend()
#define cinall(X) for (auto &i : X) cin >> i
#define printall(X) for (auto &i : X) cout << i << " "
#define printFromTo(cont, i, j, ch) for (int _ = i; _ <= j; _++) cout << cont[_] << ch
#define cinFromTo(cont, i, j) for (int _ = i; _ <= j; _++) cin >> cont[_]
#define fillFromTo(cont, i, j, x) for (int _ = i; _ <= j; _++) cont[_] = x;
#define pb push_back
#define MAKE_UNIQUE_KEEP_ORDER(vec) do { \
unordered_set<decltype((vec).front())> seen; \
(vec).erase(remove_if((vec).begin(), (vec).end(), [&](auto &val) { \
if (seen.count(val)) return true; \
seen.insert(val); \
return false; \
}), (vec).end()); \
} while(0)
#define UNIQUE_SORT(vec) do { \
sort((vec).begin(), (vec).end()); \
(vec).erase(unique((vec).begin(), (vec).end()), (vec).end()); \
} while(0)
#define yes cout << "YES\n"
#define no cout << "NO\n"
#define MIN(v) *min_element(all(v))
#define MAX(v) *max_element(all(v))
#define LB(c, x) (lower_bound((c).begin(), (c).end(), (x)) - (c).begin())
#define UB(c, x) (upper_bound((c).begin(), (c).end(), (x)) - (c).begin())
const int N = 2e5 + 5;
const int LOG = 30;
const long long INFLL = 1e18;
const int INF = 1e9;
const long double epsilon = 0.000001;
const long long mod = 1e9 + 7;
constexpr ll TEN[] = {
1LL,10LL,100LL,1000LL,10000LL,100000LL,1000000LL,10000000LL,
100000000LL,1000000000LL,10000000000LL,100000000000LL,1000000000000LL,
10000000000000LL,100000000000000LL,1000000000000000LL,10000000000000000LL,
100000000000000000LL,1000000000000000000LL,
};
long long binPowByMod(long long x, long long power, long long modx) {
long long res = 1;
long long base = x % modx;
while (power > 0) {
if (power & 1) res = (res * base) % modx;
base = (base * base) % modx;
power >>= 1;
}
return res;
}
void set_IO(string str = "")
{
if (!str.empty()) {
freopen((str + ".in").c_str(), "r", stdin);
freopen((str + ".out").c_str(), "w", stdout);
}
}
// Base type printers
void _print(long long t) { cerr << t; }
void _print(int t) { cerr << t; }
void _print(string t) { cerr << '"' << t << '"'; }
void _print(char t) { cerr << '\'' << t << '\''; }
void _print(double t) { cerr << t; }
void _print(long double t) { cerr << t; }
void _print(unsigned long long t) { cerr << t; }
void _print(bool t) { cerr << (t ? "true" : "false"); }
// STL containers
template<class T> void _print(vector<T> v) { cerr << "["; for (auto& i : v) { _print(i); cerr << " "; } cerr << "]"; }
template<class T, size_t N> void _print(array<T, N> a) { cerr << "["; for (auto& i : a) { _print(i); cerr << " "; } cerr << "]"; }
template<class T> void _print(set<T> v) { cerr << "{"; for (auto& i : v) { _print(i); cerr << " "; } cerr << "}"; }
template<class T> void _print(multiset<T> v) { cerr << "{"; for (auto& i : v) { _print(i); cerr << " "; } cerr << "}"; }
template<class T> void _print(unordered_set<T> v) { cerr << "{"; for (auto& i : v) { _print(i); cerr << " "; } cerr << "}"; }
template<class T, class V> void _print(map<T, V> v) { cerr << "{"; for (auto& i : v) { _print(i.first); cerr << ":"; _print(i.second); cerr << " "; } cerr << "}"; }
template<class T, class V> void _print(unordered_map<T, V> v) { cerr << "{"; for (auto& i : v) { _print(i.first); cerr << ":"; _print(i.second); cerr << " "; } cerr << "}"; }
template<class T, class V> void _print(pair<T, V> p) { cerr << "("; _print(p.first); cerr << ", "; _print(p.second); cerr << ")"; }
void solve()
{
int cnt = 0;
string s;
cin >> s;
int n = s.size();
for (int i = 0; i < n; i++)
{
if (cnt % 4 == 0)
{
if (s[i] == 'H')
cnt++;
}
if (cnt % 4 == 1)
{
if (s[i] == 'O')
cnt++;
}
if (cnt % 4 == 2)
{
if (s[i] == 'N')
cnt++;
}
if (cnt % 4 == 3)
{
if (s[i] == 'I')
cnt++;
}
}
cout << cnt / 4 << endl;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int t = 1;
//cin >> t;
while (t--) {
solve();
cout << endl;
}
return 0;
}
