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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...
#define NDIM 2 typedef struct particle { float x[NDIM]; float mass; struct particle *next; }Particle; // Allocate a new particle and add it to the start of the list
struct particle* newparticle(Particle *first){
  ...
» Particle *p; » p=xmalloc(sizeof *p); » p->next=first; // Now initialise exactly as before » printf("Please enter the mass and x and y values.\n"); » scanf("%f %f %f", &p->mass, &p->x[0], &p->x[1]); » return p;
} int main(){
  ...
» int i, n; » Particle *first=NULL; » printf("How many structures would you like?\n"); » scanf("%d", &n); » for (i=0; i<n; ++i) first=newparticle(first); » return 0;
}
Memory

Allocated memory

128
129
130
131
132
133
134
135
128.x[0] = -1.68642e+25
128.x[1] = 0.000374813
136
137
138
139
140
141
142
143
128.mass = 2.29709406e-38
128.next = -120791719

152
153
154
155
156
157
158
159
152.x[0] = -1.92026e+23
152.x[1] = 3.64821e+14
160
161
162
163
164
165
166
167
152.mass = 4.06936244e+35
152.next = -130692234

176
177
178
179
180
181
182
183
176.x[0] = 25301.5
176.x[1] = 1.58438e+28
184
185
186
187
188
189
190
191
176.mass = -8.02438904e+37
176.next = -123060032

200
201
202
203
204
205
206
207
200.x[0] = 1.4013e-44
200.x[1] = 0
208
209
210
211
212
213
214
215
200.mass = 0
200.next = NULL

newparticle()

348
349
350
351
first = -4154463664
360
361
362
363
p = -4290357422

newparticle()

348
349
350
351
first = NULL
360
361
362
363
p = -4290357422

newparticle()

348
349
350
351
first = -4154463640
360
361
362
363
p = -4290357422

newparticle()

348
349
350
351
first = -4154463688
360
361
362
363
p = -4290357422

main()

432
433
434
435
436
437
438
439
i = 134540174
n = 134539978
440
441
442
443
first = NULL

NB: the actual memory address of each variable is the
address shown plus 4290357424 (0xFFB9A8B0).

The actual address of allocated memory is the
address shown plus 135893608 (0x8199268).

Show Advanced options

.

Input was:

4 
4.1 2.4 7.7 
5.0 6.3 8.6 
3.6 4.3 2.91 
7.2 5.7 6.1

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

Output

How many structures would you like?
Please enter the mass and x and y values.
Please enter the mass and x and y values.
Please enter the mass and x and y values.
Please enter the mass and x and y values.
                                                                                                                                                                                                                                                                       

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