How to print all the diagonal elements of a 2d vector in C++

Question

0.00/5 (No votes)

See more:

I'm looking for a C++ way using vector to get all the diagonals of a (square) matrix, represented as a 2d vector.

    matrix = [
    [1,2,3,4],
    [5,1,2,3],
    [9,5,1,2]]

But I have trouble coming up with a way to generate all the diagonals. The output I'm looking for is:

"[9]", "[5, 5]", "[1, 1, 1]", "[2, 2, 2]", "[3, 3]", "[4]".

What I have tried:

I tried but I can only print the elements of the main diagonal. Could someone show how to print all the diagonal elements.

Posted 27-Mar-20 15:03pm

R0ber1t

Updated 28-Mar-20 0:21am

Add a Solution

Comments

John R. Shaw 28-Mar-20 1:42am

Interesting. But do not post home work questions here. Grab a pencil and paper and figure it out.
-OR-
I could put on a blind fold and see if I could do it.

Richard MacCutchan 28-Mar-20 4:46am

You just need to start from every relevant point in the matrix, and traverse the diagonal from that point. So starting in column1 go down the rows and follow each. Then follow each daigonal from column2, column3 ...

1 solution

Add a Solution

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

CPallini · Answer 1 · 2020-03-28T00:23:00

A diagonal starting at (row,0) includes all items (row+k,k) where k=0,1,.., ROWS-row-1.
In a similar way, a diagonal starting at (0,col) includes all items (k,col+k) where k=0, 1, .., COLS-col-1.

The task is competed if you iterate on rows:

row = N-1,N-2,..,0

and columns:

col = 1, 2, .., COLS-1

How to print all the diagonal elements of a 2d vector in C++

1 solution

Solution 1

Add your solution here

Preview 0

How to print all the diagonal elements of a 2d vector in C++

1 solution

Solution 1

Add your solution here

Preview 0

Existing Members

...or Join us