{"problem":{"name":"Erase and Append","description":{"content":"You are given strings $s$ and $t$ of length $N$ consisting of `0` and `1`. Determine whether it is possible to make $s$ match $t$ by performing the following operation at least $0$ and at most $N+1$ t","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"arc207_e"},"statements":[{"statement_type":"Markdown","content":"You are given strings $s$ and $t$ of length $N$ consisting of `0` and `1`. Determine whether it is possible to make $s$ match $t$ by performing the following operation at least $0$ and at most $N+1$ times, and if possible, show one such sequence of operations.\nOperation: Perform the following in order.\n\n1.  Choose integers $a$ and $b$ satisfying $1 \\le a,b \\le N$ and $|a-b|=1$\n2.  Append the $a$\\-th character from the beginning of $s$ to the end of $s$\n3.  Remove the $b$\\-th character from the beginning of $s$ and concatenate the remaining characters in their original order\n\nYou are given $T$ test cases; find the answer for each of them.\n\n## Constraints\n\n*   $1 \\le T \\le 10^{5}$\n*   $2 \\le N \\le 2 \\times 10^{5}$\n*   $s$ and $t$ are strings of length $N$ consisting of `0` and `1`.\n*   The sum of $N$ over all test cases is at most $2 \\times 10^{5}$.\n\n## Input\n\nThe input is given from Standard Input in the following format:\n\n$T$\n$\\text{case}_1$\n$\\text{case}_2$\n$\\vdots$\n$\\text{case}_T$\n\nEach test case is given in the following format:\n\n$N$\n$s$\n$t$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"arc207_e","tags":[],"sample_group":[["3\n5\n00101\n00010\n2\n01\n01\n2\n00\n11","1\n2 3\n0\n-1\n\nIn the first test case, $s$ is `00101` and $t$ is `00010`.\n\n*   By choosing $2$ and $3$ as $a$ and $b$, appending the $2$\\-nd character `0` to the end of $s$, and then removing the $3$\\-rd character, we can make $s$ and $t$ match.\n*   Note that the integers $a$ and $b$ chosen in the operation must satisfy $|a-b|=1$.\n\nIn the second test case, $s$ and $t$ can be made to match with zero operations.\nIn the third test case, no matter how the operations are performed, $s$ and $t$ cannot be made to match."]],"created_at":"2026-03-03 11:01:14"}}