HIIT remains

#include <bits/stdc++.h>
using namespace std;
#define int long long
 
string to_string(string s) {
    return '"' + s + '"';
}
 
string to_string(const char* s) {
    return to_string((string) s);
}
 
string to_string(bool b) {
    return (b ? "true" : "false");
}
 
template <typename A, typename B>
string to_string(pair<A, B> p) {
    return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
 
template <typename A>
string to_string(A v) {
    bool first = true;
    string res = "{";
    for (const auto &x : v) {
        if (!first) {
            res += ", ";
        }
        first = false;
        res += to_string(x);
    }
    res += "}";
    return res;
}
 
void debug_out() {
    cerr << endl;
}
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << " " << to_string(H);
    debug_out(T...);
}
 
#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
 
const int N = 1e5 + 5;
 
const string S = "HIIT";
 
string s;
int n;
int dp[N][5];
 
void solve() {
    cin >> s;
    n = s.size();
    s = '_' + s;
 
    for (int i = 0; i <= n; i++) {
        for (int j = 0; j <= 4; j++) {
            dp[i][j] = 0;
        }
    }
 
    dp[0][0] = 1;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < 4; j++) {
            if (s[i + 1] == S[j]) {
                // could take
                dp[i + 1][j + 1] += dp[i][j];
            }
            dp[i + 1][j] += dp[i][j];
        }
    }
 
    int ans = 0;
    for (int i = 0; i <= n; i++) {
        ans += dp[i][4];
    }
    // for (int i = 0; i <= n; i++) {
    //     for (int j = 0; j <= 4; j++) {
    //         cerr << dp[i][j] << ' ';
    //     }
    //     cerr << '\n';
    // }
    cout << ans << '\n';
}
 
signed main() {
    cin.tie(0)->sync_with_stdio(0);
 
    int t;
    cin >> t;
 
    while (t--) {
        solve();
    }
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED