Declare a one-dimensional array 'num' of type int and a two-dimensional array 'matrix' of type float digrammatically explain those arrays?

Answer 1

// one dimensional array 'num' of type int...

int num[100];

{Sorry, diagrams are not possible in wiki.answers.com, you have to use words}

This is 100 copies of an integer data type, arranged sequentially in memory. The first one is called num[0], the tenth one is called num[9], and the 100th one is called num[99].

// two dimensional array 'matrix' of type float...

float matrix[10][20];

This is 200 copies of a floating point data type, arranged sequentially in memory. The first one is called matrix[0][0], the tenth one is called matrix[9][0], the eleventh one is called matrix[0][1], and the 200th one is called matrix[9][19].

In both cases, you don't want to "think" about the arrangement of bits and bytes within each int or float. Doing so is non-portable, and can lead to problems down the road. The only safe thing you can consider is the arrangement in memory of the copies of the fundamental type int or float.