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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...
// Shrink or extend a symmetric array
float * * resizesymarray(float * *p,int oldm,int newm){
  ...
» int i; // Is the new one smaller? » for (i=newm; i<oldm; ++i) free(pi); » p=realloc(p, newm*sizeof *p); // Is the new one bigger? » for (i=oldm; i<newm; ++i) pi=malloc((i+1)*sizeof *p[i]); » return p;
} // Create a new symmetric array float * * newsymarray(int m){
  ...
» return resizesymarray(NULL, 0, m);
} // Free a symmetric array void freesymarray(float * *p,int m){
  ...
» resizesymarray(p, m, 0);
} int main(){
  ...
» float * *p=NULL; » int n, newn; » printf("Size of array (>0)?\n"); » scanf("%i", &n); » p=newsymarray(n); » p[0]0=17; » p[n-1]1=11.3; » printf("New size of array (>0)?\n"); » scanf("%i", &newn); » p=resizesymarray(p, n, newn); // Do stuff here » freesymarray(p, newn); // Do more stuff not requiring p » return 0;
}
Memory

Allocated memory

128
129
130
131
132
133
134
135
128[0] =
128[1] =
136
137
138
139
128[2] =

144
145
146
147
144[0] = 2.08086e-39

160
161
162
163
164
165
166
167
160[0] = -1.19109e-08
160[1] = 2.11344e-38

176
177
178
179
180
181
182
183
176[0] = -0.00148442
176[1] = 1.88526e-37
184
185
186
187
176[2] = 1.41962e-38

192
193
194
195
196
197
198
199
192[0] = 144
192[1] = 160
200
201
202
203
204
205
206
207
192[2] = 176
192[3] =

216
217
218
219
220
221
222
223
216[0] = 0.0057955
216[1] = 3.09474e+06
224
225
226
227
228
229
230
231
216[2] = -2.06062e-07
216[3] = 9.32071e-39

resizesymarray()

364
365
366
367
p = NULL
376
377
378
379
380
381
382
383
i = -199736
?
?
?
?
416
417
418
419
420
421
422
423
?
?
?
?
oldm = 0
424
425
426
427
newm = 3

resizesymarray()

364
365
366
367
p = -4153839320
376
377
378
379
380
381
382
383
i = -199736
?
?
?
?
416
417
418
419
420
421
422
423
?
?
?
?
oldm = 4
424
425
426
427
newm = 0

resizesymarray()

412
413
414
415
p = -4153839384
424
425
426
427
428
429
430
431
i = -199656
?
?
?
?
464
465
466
467
468
469
470
471
?
?
?
?
oldm = 3
472
473
474
475
newm = 4

newsymarray()

464
465
466
467
m = 3

freesymarray()

464
465
466
467
468
469
470
471
p = -4153839320
m = 4

main()

496
497
498
499
500
501
502
503
p = NULL
n = -143233024
504
505
506
507
newn = 1

NB: the actual memory address of each variable is the
address shown plus 4294767104 (0xFFFCF200).

The actual address of allocated memory is the
address shown plus 140927592 (0x8666268).

.

Input was:

3 4

Show output (Before looking at the output, work out what you think it put should be and see if you are right.)

Output

Size of array (>0)?
New size of array (>0)?
                                                                                                                                                                                                                                                                       

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