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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); » for ( Particle *p=first;p!=NULL; p=p->next) printf("Mass: %f position: (%g, %g)\n", p->mass, p->x[0], p->x[1]); » return 0;
}
Memory

Allocated memory

128
129
130
131
132
133
134
135
128.x[0] = -1160.56
128.x[1] = -4.90246e+09
136
137
138
139
140
141
142
143
128.mass = -1.46762061e-28
128.next = -126648898

152
153
154
155
156
157
158
159
152.x[0] = -2.36252e-29
152.x[1] = -1.80983e+22
160
161
162
163
164
165
166
167
152.mass = -2.40417583e-38
152.next = -130579271

176
177
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179
180
181
182
183
176.x[0] = -1.70626e+28
176.x[1] = 5.49752e+30
184
185
186
187
188
189
190
191
176.mass = -0.0509952568
176.next = -131920758

200
201
202
203
204
205
206
207
200.x[0] = 7.60185e-38
200.x[1] = 4.4689e+19
208
209
210
211
212
213
214
215
200.mass = -3.5961552e+35
200.next = -141622586

newparticle()

348
349
350
351
first = -4143831096
360
361
362
363
p = 504

newparticle()

348
349
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351
first = -4143831120
360
361
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363
p = 504

newparticle()

348
349
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351
first = NULL
360
361
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363
p = 504

newparticle()

348
349
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351
first = -4143831144
360
361
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363
p = 504

main()

460
461
462
463
i = 200
464
465
466
467
468
469
470
471
n = -145271993
first = NULL

main(): for()

472
473
474
475
p = -4143831072

NB: the actual memory address of each variable is the
address shown plus 4286929744 (0xFF855B50).

The actual address of allocated memory is the
address shown plus 143098472 (0x8878268).

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.
Mass: 7.200000 position: (5.7, 6.1)
Mass: 3.600000 position: (4.3, 2.91)
Mass: 5.000000 position: (6.3, 8.6)
Mass: 4.100000 position: (2.4, 7.7)
                                                                                                                                                                                                                                                                       

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