{"problem":{"name":"Call the ID Number","description":{"content":"There are $N$ people whose IDs are $1$, $2$, $\\ldots$, and $N$. Each of person $1$, person $2$, $\\ldots$, and person $N$ performs the following action once in this order: *   If person $i$'s ID has 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":"abc293_b"},"statements":[{"statement_type":"Markdown","content":"There are $N$ people whose IDs are $1$, $2$, $\\ldots$, and $N$.\nEach of person $1$, person $2$, $\\ldots$, and person $N$ performs the following action once in this order:\n\n*   If person $i$'s ID has not been called out yet, call out person $A_i$'s ID.\n\nEnumerate the IDs of all the people whose IDs are never called out until the end **in ascending order**.\n\n## Constraints\n\n*   $2 \\leq N \\leq 2 \\times 10^5$\n*   $1 \\leq A_i \\leq N$\n*   $A_i \\neq i$\n*   All values in the input are integers.\n\n## Input\n\nThe input is given from Standard Input in the following format:\n\n$N$\n$A_1$ $A_2$ $\\ldots$ $A_N$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"abc293_b","tags":[],"sample_group":[["5\n3 1 4 5 4","2\n2 4\n\nThe five people's actions are as follows.\n\n*   Person $1$'s ID has not been called out yet, so person $1$ calls out person $3$'s ID.\n*   Person $2$'s ID has not been called out yet, so person $2$ calls out person $1$'s ID.\n*   Person $3$'s ID has already been called out by person $1$, so nothing happens.\n*   Person $4$'s ID has not been called out yet, so person $4$ calls out person $5$'s ID.\n*   Person $5$'s ID has already been called out by person $4$, so nothing happens.\n\nTherefore, person $2$ and $4$'s IDs are not called out until the end."],["20\n9 7 19 7 10 4 13 9 4 8 10 15 16 3 18 19 12 13 2 12","10\n1 2 5 6 8 11 14 17 18 20"]],"created_at":"2026-03-03 11:01:14"}}