{ "data": { "question": { "questionId": "1000046", "questionFrontendId": "面试题 17.24", "categoryTitle": "LCCI", "boundTopicId": 100737, "title": "Max Submatrix LCCI", "titleSlug": "max-submatrix-lcci", "content": "

Given an NxM matrix of positive and negative integers, write code to find the submatrix with the largest possible sum.

\r\n\r\n

Return an array [r1, c1, r2, c2], where r1, c1 are the row number and the column number of the submatrix's upper left corner respectively, and r2, c2 are the row number of and the column number of lower right corner. If there are more than one answers, return any one of them.

\r\n\r\n

Note: This problem is slightly different from the original one in the book.

\r\n\r\n

Example:

\r\n\r\n
\r\nInput:\r\n[\r\n   [-1,0],\r\n   [0,-1]\r\n]\r\nOutput: [0,1,0,1]
\r\n\r\n

Note:

\r\n\r\n\r\n", "translatedTitle": "最大子矩阵", "translatedContent": "

给定一个正整数、负整数和 0 组成的 N × M 矩阵，编写代码找出元素总和最大的子矩阵。

\n\n

返回一个数组 [r1, c1, r2, c2]，其中 r1, c1 分别代表子矩阵左上角的行号和列号，r2, c2 分别代表右下角的行号和列号。若有多个满足条件的子矩阵，返回任意一个均可。

\n\n

注意：本题相对书上原题稍作改动

\n\n

示例：

\n\n
输入：\n[\n   [-1,0],\n   [0,-1]\n]\n输出：[0,1,0,1]\n解释：输入中标粗的元素即为输出所表示的矩阵
\n\n

 

\n\n

说明：

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