2214GUnreviewedunratedGPT-5.5 (xhigh)

Anomaly

Progressive hints first, then the full explanation and implementation when you're ready to cash out.

Hints

Progressive nudges

Open only as much as you need to keep the solve alive.

The input gives only $i$ , so there is no real computation hiding in the constraints. For a length- $11$ unknown string $s$ , the task is just asking for one fixed value $s_i$ .

The samples tell you $s_4=\texttt{c}$ and $s_2=\texttt{i}$ , but that is nowhere near enough. The *special, communication tags are not decorative confetti; this problem is about information being communicated outside the normal statement.

Read the note like evidence, not flavor text. It talks about a leaked answer, a disqualified person, and the editorial. That is basically the problem yelling: “the solution is in the post-contest story.”

The “leak” was encoded by a weird submission order. Since the contest has problems $A$ through $J$ , a sequence of problem letters can encode lowercase letters from $\texttt{a}$ to $\texttt{j}$ .

B,I,G,C,H,A,D,J,E,F,F

Editorial

Full explanation

Open this when you want the whole argument, complexity included.

Key Observation

This is an April Fools communication problem, so trying to derive the string from the input is a trap. The input contains only an index $i$ , and the statement gives no deterministic rule for computing the hidden string. So the “algorithm” must know the fixed hidden string.

The post-contest official Codeforces tutorial reveals that the hidden string is

s = \texttt{bigchadjeff}.

The joke explanation is that a disqualified user communicated the answer by submitting to problems in the order

B,I,G,C,H,A,D,J,E,F,F,

which, when read as lowercase letters, spells

\texttt{bigchadjeff}.

The sample checks out:

s_4 = \texttt{c}, \qquad s_2 = \texttt{i}.

Algorithm

Store the string $s=\texttt{bigchadjeff}$ . For each test case, read $i$ and output the $(i-1)$ -th character in $0$ -indexed C++ notation:

\operatorname{ans}(i)=s[i-1].

That is it. Peak competitive programming: hardcode the lore and collect AC.

Complexity

For $t$ test cases, each query is answered in $O(1)$ time.

T = O(t), \qquad M = O(1).

Solution

Generated C++

This is the full implementation the model produced for the problem.

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

using ll = long long;

void setIO() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
}

int main() {
    setIO();

    const string s = "bigchadjeff";

    int t;
    cin >> t;
    while (t--) {
        int i;
        cin >> i;
        cout << s[i - 1] << '\n';
    }

    return 0;
}

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

using ll = long long;

void setIO() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
}

int main() {
    setIO();

    const string s = "bigchadjeff";

    int t;
    cin >> t;
    while (t--) {
        int i;
        cin >> i;
        cout << s[i - 1] << '\n';
    }

    return 0;
}

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