#include <bits/stdc++.h>
using namespace std;

#define ALL(v) v.begin(), v.end()
#define V vector
#define P pair
using ll = long long;
using ld = long double;
const int MOD = 1e9+7;
const ll INF = 1LL << 60;


int main() {
    string s; cin >> s;

    if(s == "hi" || s == "hihi" || s == "hihihi" || s == "hihihihi" || s == "hihihihihi") cout << "Yes" << endl;
    else cout << "No" << endl;

    return 0;
}

#include <bits/stdc++.h>
using namespace std;

int main() {
    string S;
    cin >> S;

    bool ok = true;
    if (S.size() % 2 == 1) ok = false;
    for (int i = 0; i < S.size() / 2; i += 2) {
        if (S.substr(i, 2) != "hi") {
            ok = false;
        }
    }

    if(ok) cout << "Yes" << endl;
    else cout << "No" << endl;
}