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2008-11-03T05:19:19Z

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==='''Lab3'''===

===Question 1===

For question one I made a loop for the arralist_push function, to change the array value to zero, 10 million times.
Here is my code.

<pre>
int main() {
ArrayList arra;
int i;
arraylist_init(&arra);
int clock1,clock2;

clock1 = clock();
for(i=0;i<10000000;i++){
arraylist_push(&arra, 0);
}
clock2=clock();
printf("%d ms", (clock2-clock1));

return 0;
}
</pre>

The result ranged from 550-640ms.

===Question 2===

For question two I changed the growth factor to a variety of numbers.

<pre>
'''OUTPUT'''

*3 Growth Factor -
The for loop of 10 million loops took 594 ms.

*9^99999 GF -
The for loop of 10 million loops took 531 ms.

*1 - Error -
/usr/bin/bash: line 1: 5576 Segmentation fault (core dumped) ./arraylist2.exe.

*1.1 -
The for loop of 10 million loops took 1204 ms.

*1.2 -
The for loop of 10 million loops took 890 ms.

*1.3 -
The for loop of 10 million loops took 750 ms.

*1.4 -
The for loop of 10 million loops took 672 ms.
</pre>

===Question 3===

For this question the starting allocation for the array needed to be changed to various numbers.

<pre>
'''OUTPUT'''
''Original minimum allocation = 16''

Minimum Allocation of 1 - The for loop of 10 million loops took 562 ms.

Minimum Allocation of 100 - The for loop of 10 million loops took 594 ms.

Minimum Allocation of 99999 - The for loop of 10 million loops took 531 ms.

Minimum Allocation of 0.01 - /usr/bin/bash: line 1: 5576 Segmentation fault (core dumped) ./arraylist3.exe.
</pre>
The results suggest that the starting allocation does not affect the time it takes to do the loop 10 million times.
</pre>

===Question 4===

Experiment 1 was repeated but with the added code of using the function "ensure_capacity" to allocate memory (initially) according to the number of loops in the for loop (10 million).
<pre>
Partial Code

ensure_capacity(&arra,10000000);
</pre>

The output was faster than normal.
<pre>
'''OUTPUT'''
The for loop of 10 million loops took 437 ms.
</pre>

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