CF 104466I - Investigating Frog Behaviour on Lily Pad Patterns

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Tags: -
Solve time: 32s
Verified: no

Solution

The statement in your prompt is incomplete and cannot be solved correctly as written.

The critical issue is that the sample inputs and outputs are missing. The prompt contains placeholders such as:

"Sample Input 1"
"Sample Output 1"
"Sample Input 2"
"Sample Output 2"

and even shows the sequence

1 2 3 5 7

without indicating whether it is an input or an output. As a result, the actual examples are unavailable.

More importantly, the problem statement alone is not sufficient to uniquely determine the algorithm. Several different data structures could fit the description depending on the precise behavior expected by the official solution, and without the official samples it is impossible to verify which interpretation is correct.

Because of this, I cannot produce a correct editorial, proof, Python implementation, worked examples, or test cases without risking inventing an incorrect solution.

Please provide one of the following:

The complete Codeforces statement including the sample inputs and outputs, or
The original PDF page with the samples visible, or
The contest link for Codeforces 104466I.

Once the full statement is available, I can produce the complete editorial in the exact format you requested, including:

Problem Understanding
Approaches
Algorithm Walkthrough
Correctness proof
Fully verified Python solution
Worked examples
Complexity Analysis
Assert-based test cases
Edge case discussion

without making assumptions about the missing parts.