TopCoder

User's AC Ratio

NaN% (0/0)

Submission's AC Ratio

NaN% (0/0)

Tags

Description

Given a two-dimensional array of positive and negative integers, a sub-rectangle is any contiguous sub-array of size
1 × 1 or greater located within the whole array. The sum of a rectangle is the sum of all the elements in that
rectangle. In this problem the sub-rectangle with the largest sum is referred to as the maximal sub-rectangle.
As an example, the maximal sub-rectangle of the array:


0 –2 –7 0

9 2 –6 2

-4 1 –4 1

-1 8 0 –2


is in the lower left corner:


9 2

-4 1

-1 8


and has a sum of 15.

Input Format

The input consists of an N × N array of integers. The input begins with a single positive integer N on a line by itself,
indicating the size of the square two-dimensional array. This is followed by N 2 integers separated by whitespace
(spaces and newlines). These are the N 2 integers of the array, presented in row-major order. That is, all numbers in
the first row, left to right, then all numbers in the second row, left to right, etc. N may be as large as 100. The
numbers in the array will be in the range [-127,127].

Output Format

Output the sum of the maximal sub-rectangle.

Sample Input 1

4
0 -2 -7 0 9 2 -6 2
-4 1 -4 1 -1

8 0 -2

Sample Output 1

15

Hints

Problem Source

Migrated from old NTUJ.

Subtasks

No. Testdata Range Score

Testdata and Limits

No. Time Limit (ms) Memory Limit (VSS, KiB) Output Limit (KiB) Subtasks
0 10000 65536 20