{"problem":{"name":"Doubled","description":{"content":"Given is an integer $N$.   How many integers $x$ between $1$ and $N$ (inclusive) satisfy the following condition? *   The decimal representation (without leading zeros) of $x$ has an even number of d","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"abc196_c"},"statements":[{"statement_type":"Markdown","content":"Given is an integer $N$.  \nHow many integers $x$ between $1$ and $N$ (inclusive) satisfy the following condition?\n\n*   The decimal representation (without leading zeros) of $x$ has an even number of digits, and its first and second halves are equal as strings.\n\n## Constraints\n\n*   $N$ is an integer.\n*   $1 ≤ N < 10^{12}$\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$N$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"abc196_c","tags":[],"sample_group":[["33","3\n\nThree numbers $11$, $22$, and $33$ satisfy the condition."],["1333","13\n\nFor example, the decimal representation of $1313$ has four digits, and its first and second halves are both $13$, so $1313$ satisfies the condition."],["10000000","999"]],"created_at":"2026-03-03 11:01:13"}}