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Question

Write a program to convert a 2D array “A” to 1D array “a” using row-major order and column-major order

Answer 1

The size of a 1D array corresponding to a 2D array would be
columns * rows,
and the indexing can be converted by using the formula
row * totalColumns + column.
The rest is simple copy pasta by using for loops, either you iterate over the rows before the columns for a row major order in the 1D array, or you iterate over the columns before the rows for a column major order.

Example program:
https://code.sololearn.com/c45xDJNiG87C/?ref=app