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copied!<p>I am sure your compiler told you what was wrong.</p> <p>You are passing a <code>long**</code> to a function that expects a <code>int*</code> at the line</p> <pre><code>fill_array(&arrayIn, n); </code></pre> <p>function prototype is</p> <pre><code>void fill_array(int *arr, int n) </code></pre> <p>Same problem with the other function. From there, anything can happen.</p> <p>Always, ALWAYS heed the warnings your compiler gives you.</p> <p><strong>MAJOR EDIT</strong></p> <p>First - yes, the name of an array is already a pointer.</p> <p>Second - declare a function prototype at the start of your code; then the compiler will throw you helpful messages which will help you catch these</p> <p>Third - if you want to pass the address of a simple variable to a function, there is no need for a <code>malloc</code>; just use the address of the variable.</p> <p>Fourth - the <code>rand()</code> function returns an integer between 0 and <code>RAND_MAX</code>. The code</p> <pre><code>a[i] = (RAND_MAX + 1) * rand() + rand(); </code></pre> <p>is a roundabout way of getting </p> <pre><code>a[i] = rand(); </code></pre> <p>since <code>(RAND_MAX + 1)</code> will overflow and give you zero... If you actually wanted to be able to get a "really big" random number, you would have to do the following:</p> <p>1) make sure <code>a</code> is a <code>long *</code> (with the correct prototypes etc)</p> <p>2) convert the numbers before adding / multiplying: </p> <pre><code>a[i] = (RAND_MAX + 1L) * rand() + rand(); </code></pre> <p>might do it - or maybe you need to do some more casting to <code>(long)</code>; I can never remember my order of precedence so I usually would do</p> <pre><code>a[i] = ((long)(RAND_MAX) + 1L) * (long)rand() + (long)rand(); </code></pre> <p>to be 100% sure.</p> <p>Putting these and other lessons together, here is an edited version of your code that compiles and runs (I did have to "invent" a <code>print_array</code>) - I have written comments where the code needed changing to work. The last point above (making long random numbers) was not taken into account in this code yet.</p> <pre><code>#include <stdio.h> #include <stdlib.h> // include prototypes - it helps the compiler flag errors: void fill_array(int *arr, int n); void InsertionSort(int *arr, int n, int *swap_count, int *compare_count); void print_array(int *arr, int n, int *swap_count, int *compare_count); int main(void) { // change data type to match function int *arrayIn; // instead of mallocing, use a fixed location: int swap_count, compare_count; // often a good idea to give your pointers a _p name: int *swap_count_p = &swap_count; int *compare_count_p = &compare_count; // the pointer must not be set to zero: it's the CONTENTs that you set to zero *compare_count_p = 0; *swap_count_p = 0; int i, j; for (j = 10; j <= 1000; j*=10) { for (i = 1; i <= 5; i++){ if (i == 1 || i == 2 || i == 5) { int n = i * j; arrayIn = malloc(sizeof(long)*n); fill_array(arrayIn, n); InsertionSort(arrayIn, n, swap_count_p, compare_count_p); print_array(arrayIn, n, swap_count_p, compare_count_p); swap_count = 0; compare_count = 0; free(arrayIn); } } } return 0; } void fill_array(int *arr, int n) { int i; for (i = 0; i < n; i++) { // arr[i] = (RAND_MAX + 1)*rand() + rand(); // causes integer overflow arr[i] = rand(); } } void InsertionSort(int *arr, int n, int *swap_count, int *compare_count) { int i, j, t; for (j = 0; j < n; j++) { (*compare_count)++; t = arr[j]; i = j - 1; *swap_count = *swap_count + 2; while (i >= 0 && arr[i]>t) { //tady chybí compare_count inkrementace *compare_count = *compare_count + 2; arr[i + 1] = arr[i]; (*swap_count)++; i--; (*swap_count)++; } arr[i + 1] = t; (*swap_count)++; } } void print_array(int *a, int n, int* sw, int *cc) { int ii; for(ii = 0; ii < n; ii++) { if(ii%20 == 0) printf("\n"); printf("%d ", a[ii]); } printf("\n\nThis took %d swaps and %d comparisons\n\n", *sw, *cc); } </code></pre>

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