converting the index of 1D array into 2D array

Question

How can I convert the index of 1D array into 2D array? I know how to convert a 2D array into 1D (i*the size of row+j). I want the opposite of that.

Can you share some code and an example of what you're trying to achieve? It's a bit hard to follow the question as it's currently phrased. — Mureinik
– Mureinik, Commented Jan 2, 2017 at 21:00

Thomas Voß · Accepted Answer · 2017-01-02 21:11:41Z

5

What you need to know is: How many columns should the 2D array have: Lets say you have an array of 20 columns and 10 rows (array[20,10]):

int index  = 47;
int numberOfColumns = 20;
int column = index % numberOfColumns;
int row    = index / numberOfColumns;

// column == 7
// row    == 2

answered Jan 2, 2017 at 21:07

Thomas Voß

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Comments

Anil M · Accepted Answer · 2017-01-02 21:02:20Z

1

You can just do the opposite. if n is the length of the row and x is index in 1D. You can index like

array[x/n][x%n]

answered Jan 2, 2017 at 21:02

Anil M

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