{ "data": { "question": { "questionId": "3552", "questionFrontendId": "3260", "categoryTitle": "Algorithms", "boundTopicId": 2883082, "title": "Find the Largest Palindrome Divisible by K", "titleSlug": "find-the-largest-palindrome-divisible-by-k", "content": "

You are given two positive integers n and k.

\n\n

An integer x is called k-palindromic if:

\n\n\n\n

Return the largest integer having n digits (as a string) that is k-palindromic.

\n\n

Note that the integer must not have leading zeros.

\n\n

 

\n

Example 1:

\n\n
\n

Input: n = 3, k = 5

\n\n

Output: "595"

\n\n

Explanation:

\n\n

595 is the largest k-palindromic integer with 3 digits.

\n
\n\n

Example 2:

\n\n
\n

Input: n = 1, k = 4

\n\n

Output: "8"

\n\n

Explanation:

\n\n

4 and 8 are the only k-palindromic integers with 1 digit.

\n
\n\n

Example 3:

\n\n
\n

Input: n = 5, k = 6

\n\n

Output: "89898"

\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "找出最大的 N 位 K 回文数", "translatedContent": "

给你两个 正整数 nk

\n\n

如果整数 x 满足以下全部条件,则该整数是一个 k 回文数

\n\n\n\n

以字符串形式返回 最大的  nk 回文数

\n\n

注意,该整数 含前导零。

\n\n

 

\n\n

示例 1:

\n\n
\n

输入: n = 3, k = 5

\n\n

输出: \"595\"

\n\n

解释:

\n\n

595 是最大的 3 位 k 回文数。

\n
\n\n

示例 2:

\n\n
\n

输入: n = 1, k = 4

\n\n

输出: \"8\"

\n\n

解释:

\n\n

1 位 k 回文数只有 4 和 8。

\n
\n\n

示例 3:

\n\n
\n

输入: n = 5, k = 6

\n\n

输出: \"89898\"

\n
\n\n

 

\n\n

提示:

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