{"problem":{"name":"log2(N)","description":{"content":"Given a positive integer $N$, find the maximum integer $k$ such that $2^k \\le N$.","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"abc215_b"},"statements":[{"statement_type":"Markdown","content":"Given a positive integer $N$, find the maximum integer $k$ such that $2^k \\le N$.\n\n## Constraints\n\n*   $N$ is an integer satisfying $1 \\le N \\le 10^{18}$.\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":"abc215_b","tags":[],"sample_group":[["6","2\n\n*   $k=2$ satisfies $2^2=4 \\le 6$.\n*   For every integer $k$ such that $k \\ge 3$, $2^k > 6$ holds.\n\nTherefore, the answer is $k=2$."],["1","0\n\nNote that $2^0=1$."],["1000000000000000000","59\n\nThe input value may not fit into a $32$\\-bit integer."]],"created_at":"2026-03-03 11:01:13"}}