Day 6EasySmart Interviews

Matrix Row and Column Sums

Streaming Input / 1D Array SimulationSolved Oct 23, 2025

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Problem

Problem Description (Combined)

Given a matrix of size N × M, the task is to perform two separate calculations:

Row Sum: Print the sum of elements for each row. Constraint: Solve this without declaring or storing the full N × M matrix (i.e., streaming).
Column Sum: Print the sum of elements for each column.

Solve it yourself before you look

Reading the solution first feels like progress, but it makes the next similar problem — and the interview version — much harder, because you skipped the part where you figure it out. Give it an honest 20–30 minutes. Stuck? Re-read the pattern, watch the concept video, or try the brute force first.

Hidden: approach · solution code

Problem Description (Combined)

Solve it yourself before you look

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