Problem 56060. Sub-Diagonal Sum

Given a (m x n) matrix and a value r {1,-1}, change every element to the sum of the diagonal led by the element.
r=1 > regular diagonal (top left to bottom right)
r=-1 > flipped/cross diagonal (top right to bottom left)
in=[1 2 3 4
5 6 7 8
1 3 2 0]
r=1
out=[9 9 11 4
8 8 7 8
1 3 2 0]
%explaination
(1,1) diagonal - [1 6 2], sum = 9
(1,3) diagonal - [3 8], sum = 11
(2,1) diagonal - [5 3], sum = 8
(2,4) diagonal - [8], sum = 8
in=[1 -2 3 -4
5 -6 7 -8
1 3 -2 0]
r=-1
out=[1 3 -2 6
5 -5 10 -10
1 3 -2 0]
%explaination
(1,1) diagonal - [1], sum = 1
(1,3) diagonal - [3 -6 1], sum = -2
(2,2) diagonal - [-6 1], sum = -5
(2,4) diagonal - [-8 -2], sum = -10
Solve

Solution Stats

38.71% Correct | 61.29% Incorrect
Last Solution submitted on Sep 22, 2025

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