C program

EMPS intranet

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...
// Flawed attempt at multiple memory allocations

#define M 3
 int main(){
   ... 

»  int n;
»  float *p;

»  printf("Size of each vector?\n");
»  scanf("%d", &n);// Find the row size

»  for ( int i=0;i<M; ++i) 
    p=xmalloc(n*sizeof *p);// Allocate rows

  // Do something useful...

»  return 0;
}

Memory

Allocated memory

128	129	130	131	132	133	134	135
128[0] = 1.75848e-37				128[1] = 2.20341e-39


144	145	146	147	148	149	150	151
144[0] = 1.13984e+20				144[1] = 2.23353e-38


160	161	162	163	164	165	166	167
160[0] = -0.000160685				160[1] = 1.14236e-38

main()
296	297	298	299	300	301	302	303
n = 134536703				p = -4152352605

main(): for()
304	305	306	307
i = 0

NB: the actual memory address of each variable is the
address shown plus 4286889112 (0xFF84BC98).

The actual address of allocated memory is the
address shown plus 164991592 (0x9D59268).

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Input was:

2 4

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Output

Size of each vector?

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Code

Allocated memory

main()

main(): for()

Output