{ "data": { "question": { "questionId": "3164", "questionFrontendId": "2899", "categoryTitle": "Algorithms", "boundTopicId": 2480185, "title": "Last Visited Integers", "titleSlug": "last-visited-integers", "content": "

Given a 0-indexed array of strings words where words[i] is either a positive integer represented as a string or the string "prev".

\n\n

Start iterating from the beginning of the array; for every "prev" string seen in words, find the last visited integer in words which is defined as follows:

\n\n\n\n

Return an integer array containing the last visited integers.

\n\n

 

\n

Example 1:

\n\n
\nInput: words = ["1","2","prev","prev","prev"]\nOutput: [2,1,-1]\nExplanation: \nFor "prev" at index = 2, last visited integer will be 2 as here the number of consecutive "prev" strings is 1, and in the array reverse_nums, 2 will be the first element.\nFor "prev" at index = 3, last visited integer will be 1 as there are a total of two consecutive "prev" strings including this "prev" which are visited, and 1 is the second last visited integer.\nFor "prev" at index = 4, last visited integer will be -1 as there are a total of three consecutive "prev" strings including this "prev" which are visited, but the total number of integers visited is two.\n
\n\n

Example 2:

\n\n
\nInput: words = ["1","prev","2","prev","prev"]\nOutput: [1,2,1]\nExplanation:\nFor "prev" at index = 1, last visited integer will be 1.\nFor "prev" at index = 3, last visited integer will be 2.\nFor "prev" at index = 4, last visited integer will be 1 as there are a total of two consecutive "prev" strings including this "prev" which are visited, and 1 is the second last visited integer.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "上一个遍历的整数", "translatedContent": "

给你一个下标从 0 开始的字符串数组 words ，其中 words[i] 要么是一个字符串形式的正整数，要么是字符串 \"prev\" 。

\n\n

我们从数组的开头开始遍历，对于 words 中的每个 \"prev\" 字符串，找到 words 中的 上一个遍历的整数 ，定义如下：

\n\n\n\n

请你返回一个整数数组，包含所有上一个遍历的整数。

\n\n

 

\n\n

示例 1：

\n\n
\n输入：words = [\"1\",\"2\",\"prev\",\"prev\",\"prev\"]\n输出：[2,1,-1]\n解释：\n对于下标为 2 处的 \"prev\" ，上一个遍历的整数是 2 ，因为连续 \"prev\" 数目为 1 ，同时在数组 reverse_nums 中，第一个元素是 2 。\n对于下标为 3 处的 \"prev\" ，上一个遍历的整数是 1 ，因为连续 \"prev\" 数目为 2 ，同时在数组 reverse_nums 中，第二个元素是 1 。\n对于下标为 4 处的 \"prev\" ，上一个遍历的整数是 -1 ，因为连续 \"prev\" 数目为 3 ，但总共只遍历过 2 个整数。\n
\n\n

示例 2：

\n\n
\n输入：words = [\"1\",\"prev\",\"2\",\"prev\",\"prev\"]\n输出：[1,2,1]\n解释：\n对于下标为 1 处的 \"prev\" ，上一个遍历的整数是 1 。\n对于下标为 3 处的 \"prev\" ，上一个遍历的整数是 2 。\n对于下标为 4 处的 \"prev\" ，上一个遍历的整数是 1 ，因为连续 \"prev\" 数目为 2 ，同时在数组 reverse_nums 中，第二个元素是 1 。\n
\n\n

 

\n\n

提示：

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