Questions regarding default integer value : <p>I noticed some differences when I make some minor changes on the following codes:</p>

<pre><code>#include&lt;stdio.h&gt;

 int main()
 {
    int arrow;
    printf("%d\n", arrow);
    int wheel[12]={17, 38, 23, 17, 19, 41, 13, 17, 12, 11, 15, 23};
    int initialValue = wheel[arrow];
    printf("%d\n", initialValue);
    arrow = (arrow + 1) % 12;
    printf("%d\n", arrow);
 }
</code></pre>

<p>As I erased the final two rows the initial value of arrow is 1 which corresponds to the value '38' in the array. However, with the complete code the initial value of arrow turns to 0, which points to the value '17' in the array. I want to know why that is the case?</p>

<p>Thanks a lot!</p>
