{"problem":{"name":"A. Quasi-palindrome","description":{"content":"Let _quasi-palindromic_ number be such number that adding some leading zeros (possible none) to it produces a palindromic string. String _t_ is called a palindrome, if it reads the same from left to ","description_type":"Markdown"},"platform":"Codeforces","limit":{"time_limit":1000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"CF863A"},"statements":[{"statement_type":"Markdown","content":"Let _quasi-palindromic_ number be such number that adding some leading zeros (possible none) to it produces a palindromic string.\n\nString _t_ is called a palindrome, if it reads the same from left to right and from right to left.\n\nFor example, numbers 131 and 2010200 are _quasi-palindromic_, they can be transformed to strings \"131\" and \"002010200\", respectively, which are palindromes.\n\nYou are given some integer number _x_. Check if it's a _quasi-palindromic_ number.\n\n## Input\n\nThe first line contains one integer number _x_ (1 ≤ _x_ ≤ 109). This number is given without any leading zeroes.\n\n## Output\n\nPrint \"_YES_\" if number _x_ is _quasi-palindromic_. Otherwise, print \"_NO_\" (without quotes).\n\n[samples]","is_translate":false,"language":"English"},{"statement_type":"Markdown","content":"定义一个 _quasi-palindromic_ 数为：通过添加若干前导零（可能不添加）后，可以变为回文字符串的数。\n\n字符串 #cf_span[t] 被称为回文，如果它从左到右读和从右到左读是一样的。\n\n例如，数字 #cf_span[131] 和 #cf_span[2010200] 是 _quasi-palindromic_ 数，它们可以分别变为字符串 \"#cf_span[131]\" 和 \"#cf_span[002010200]\"，这两个都是回文。\n\n给你一个整数 #cf_span[x]，判断它是否是 _quasi-palindromic_ 数。\n\n第一行包含一个整数 #cf_span[x]（#cf_span[1 ≤ x ≤ 10^9]）。这个数以没有前导零的形式给出。\n\n如果 #cf_span[x] 是 _quasi-palindromic_ 数，则输出 \"_YES_\"；否则输出 \"_NO_\"（不包含引号）。\n\n## Input\n\n第一行包含一个整数 #cf_span[x]（#cf_span[1 ≤ x ≤ 10^9]）。这个数以没有前导零的形式给出。\n\n## Output\n\n如果 #cf_span[x] 是 _quasi-palindromic_ 数，则输出 \"_YES_\"；否则输出 \"_NO_\"（不包含引号）。\n\n[samples]","is_translate":true,"language":"Chinese"},{"statement_type":"Markdown","content":"**Definitions**  \nLet $ x \\in \\mathbb{Z} $ be a positive integer with $ 1 \\leq x \\leq 10^9 $, represented in base-10 without leading zeros.  \nLet $ s \\in \\{0,1,\\dots,9\\}^* $ be the decimal string representation of $ x $ (no leading zeros).  \n\n**Constraints**  \n- $ s $ contains no leading zeros.  \n- $ 1 \\leq |s| \\leq 10 $.  \n\n**Objective**  \nDetermine whether there exists a string $ s' \\in \\{0,1,\\dots,9\\}^* $ such that:  \n- $ s' = 0^k \\cdot s $ for some $ k \\geq 0 $,  \n- $ s' $ is a palindrome (i.e., $ s' = \\text{reverse}(s') $).  \n\nOutput \"YES\" if such $ s' $ exists; otherwise, output \"NO\".","is_translate":false,"language":"Formal"}],"meta":{"iden":"CF863A","tags":["brute force","implementation"],"sample_group":[["131","YES"],["320","NO"],["2010200","YES"]],"created_at":"2026-03-03 11:00:39"}}