{"problem":{"name":"9x9","description":{"content":"Having learned the multiplication table, Takahashi can multiply two integers between $1$ and $9$ (inclusive) together. He cannot do any other calculation. Given are two integers $A$ and $B$. If Takaha","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"abc144_a"},"statements":[{"statement_type":"Markdown","content":"Having learned the multiplication table, Takahashi can multiply two integers between $1$ and $9$ (inclusive) together. He cannot do any other calculation.\nGiven are two integers $A$ and $B$.\nIf Takahashi can calculate $A \\times B$, print the result; if he cannot, print `-1` instead.\n\n## Constraints\n\n*   $1 \\leq A \\leq 20$\n*   $1 \\leq B \\leq 20$\n*   All values in input are integers.\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$A$ $B$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"abc144_a","tags":[],"sample_group":[["2 5","10\n\n$2 \\times 5 = 10$."],["5 10","\\-1\n\n$5\\times 10 = 50$, but Takahashi cannot do this calculation, so print `-1` instead."],["9 9","81"]],"created_at":"2026-03-03 11:01:14"}}