{ "data": { "question": { "questionId": "2298", "questionFrontendId": "2180", "categoryTitle": "Algorithms", "boundTopicId": 1274497, "title": "Count Integers With Even Digit Sum", "titleSlug": "count-integers-with-even-digit-sum", "content": "

Given a positive integer num, return the number of positive integers less than or equal to num whose digit sums are even.

\n\n

The digit sum of a positive integer is the sum of all its digits.

\n\n

 

\n

Example 1:

\n\n
\nInput: num = 4\nOutput: 2\nExplanation:\nThe only integers less than or equal to 4 whose digit sums are even are 2 and 4.    \n
\n\n

Example 2:

\n\n
\nInput: num = 30\nOutput: 14\nExplanation:\nThe 14 integers less than or equal to 30 whose digit sums are even are\n2, 4, 6, 8, 11, 13, 15, 17, 19, 20, 22, 24, 26, and 28.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "统计各位数字之和为偶数的整数个数", "translatedContent": "

给你一个正整数 num ，请你统计并返回 小于或等于 num 且各位数字之和为 偶数 的正整数的数目。

\n\n

正整数的 各位数字之和 是其所有位上的对应数字相加的结果。

\n\n

 

\n\n

示例 1：

\n\n
\n输入：num = 4\n输出：2\n解释：\n只有 2 和 4 满足小于等于 4 且各位数字之和为偶数。    \n
\n\n

示例 2：

\n\n
\n输入：num = 30\n输出：14\n解释：\n只有 14 个整数满足小于等于 30 且各位数字之和为偶数，分别是： \n2、4、6、8、11、13、15、17、19、20、22、24、26 和 28 。\n
\n\n

 

\n\n

提示：

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