C program

EMPS intranet

Note

This code has been compiled to show the internal calculations of the addresses of array elements like this: 824.

Hi! Hi! Start main()

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Value and type of last evaluated expression: Address of array element: Address of array elementx: (none)

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Code

 Header...
// Check display of arrays v pointers

#define LEN 4
 int main(){
   ... 

»  float * * *p=NULL;
»  int arr[2][2][2];

»  p=malloc(2*sizeof *p);
  // p[0] = malloc(LEN * sizeof *p[0]);
»  p1=malloc(LEN*sizeof *p[1]);
»  p[1]2=malloc(LEN*sizeof *p[1][2]);

»  p[1][2]3=13.1;

»  arr[1][1]0=1.7;

»  printf("%d\n", arr110);

»  return 0;
}

Memory

Allocated memory

128	129	130	131	132	133	134	135
128[0] = 1556774808				128[1] =


144	145	146	147	148	149	150	151
144[0] = 1023656785				144[1] = 173390380
152	153	154	155	156	157	158	159
144[2] = 334438584				144[3] =


168	169	170	171	172	173	174	175
168[0] = 4.77587e+28				168[1] = -4.99621e+37
176	177	178	179	180	181	182	183
168[2] = 5.75607e+12				168[3] = 1.70888e-38

main()
312	313	314	315	316	317	318	319
p = NULL				arr[0][0][0] = 1
320	321	322	323	324	325	326	327
arr[0][0][1] = -6192364				arr[0][1][0] = -144757336
328	329	330	331	332	333	334	335
arr[0][1][1] = 1				arr[1][0][0] = 200
336	337	338	339	340	341	342	343
arr[1][0][1] = -144420025				arr[1][1][0] = -143028224
344	345	346	347
arr[1][1][1] = 1

NB: the actual memory address of each variable is the
address shown plus 4288774528 (0xFFA18180).

The actual address of allocated memory is the
address shown plus 144204376 (0x8986258).

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Output

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Note

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Code

Allocated memory

main()

Output