Question

Question1

Match the variables with the location and memory layout given the following declarations:

int numbers1[5][4];

int * numbers2 = malloc (5*4*sizeof(int));

int ** numbers3 = malloc (5 * sizeof(int *));

for (int r = 0; r < 5; r++) {

numbers3[r] = malloc(4 * sizeof(int));

}

stack is static (fixed size) memory, heap is dynamic memory (allocated by the program at run time with malloc, calloc, etc)

contiguous memory is memory that is all in one place. All values in a 2D contiguous array are guaranteed to be located in the same place in memory one after another.

numbers1 is stack/ heap contiguous /non-contiguous

numbers2 is stack/ heap contiguous /non-contiguous

numbers3 is stack/ heap contiguous /non-contiguous

Answer 1

int numbrs1 [5][4];

this is a 2d array and it clearly give instruction to declare 20 integers so size is fixed and as this is an array so it allocated contiguous memory

so for numbers1 is stack and contiguous is the right option

int * numbers2 = malloc( 5* 4* sizeof(int));

this is a instruction which tells that a memory of 20 integers to be declared but this is not giving instruction to declare now,

so this get space in heap as this is allocated in dynamic memory and malloc allocates all the size as a complete chunk

so for numbers2 is heap and contiguous is the right option

int **numbers3= malloc( 5* sizeof(int *));

this is telling that we have to allocate a chunk equal to 5* pointer to int

so as this is dynamic allocation so it required heap

now for contiguous and non contiguous see that

numbers3 [r] = malloc( 4* sizeof( int));

so it will allocate a chunk of 4 integer for numbers3[0] , numbers3[1] , numbers3[2] , numbers3[3] , numbers3[4]

but these all statement are different so 5 different chunks of 4 integers are allocated , it can not be guranteed that all chunks get allocated contiguous so

for numbers3 is heap and non-contiguous

I hope this will help you so please give positive ratings :)))