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POShould be slower, but is faster. Why?
 

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  1. POShould be slower, but is faster. Why?
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    <p>Ok, so let me explain a little bit about this. In array SL[] i got pointer to lists ( I can say that the list is divided to small parts). So i go to SL[0] explore the list, then go to SL[1] explore the list..... </p> <pre><code>typedef struct TSL { struct TSL *next; int a; } LSL; LSL* SL[n] = {0}; // Array of pointers ;) // Loop 1 void Find_All_Arc_SL() { int i; LSL *tmp; for(i=0;i&lt;n;i++) { tmp = SL[i]; while(tmp != 0) { //printf("I find arc! %d -&gt; %d",i,tmp-&gt;a); tmp = tmp -&gt; next; } } } </code></pre> <p>Loop 2. </p> <pre><code>typedef struct TAL { struct TAL *next; int v; int a; } LAL; LAL *AL = 0; void Find_All_Arc_AL() { LAL *tmp; tmp = AL; while(tmp != 0) { //printf("I find arc %d -&gt; %d \n",tmp-&gt;v,tmp-&gt;a); tmp = tmp -&gt; next; }; } </code></pre> <p>In this function i just explore list... just do it without any array etc.</p> <p><strong>My question is:</strong> Why <code>Find_All_Arc_SL()</code> is always faster (milliseconds) than <code>Find_All_Arc_AL()</code>? These functions are working almost the same, but the first (faster one) one have to do additional work</p> <p><strong>YOU ASKED FOR FULL CODE. HERE IT IS:</strong> U can increase/decrease <strong>n</strong></p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;windows.h&gt; #define n 5500 //Define struct typedef struct TSL { struct TSL *next; int a; } LSL; typedef struct TAL { struct TAL *next; int v; int a; } LAL; // Poiner and array of pointers LAL *AL = 0; LSL* SL[n] = {0}; // To Calculate time __int64 freq, start, end, diff; // Build graph void Create_AL() { LAL *tmp; int p,k; for(p=0;p&lt;n;p++) for(k=0;k&lt;n;k++) { // Add arc tmp = malloc (sizeof(LAL)); tmp-&gt;v = p; tmp-&gt;a = k; if(AL == 0) { tmp-&gt;next = 0; AL = tmp; } else { tmp-&gt;next = AL; AL = tmp; } } } // Find arc void Find_All_Arc_AL() { LAL *tmp; tmp = AL; while(tmp != 0) { //printf("I found arc %d -&gt; %d \n",tmp-&gt;v,tmp-&gt;a); tmp = tmp -&gt; next; }; } // Build graph void Create_SL() { LSL *tmp; int p,k; for(p=0;p&lt;n;p++) for(k=0;k&lt;n;k++) { // Add arc tmp = malloc(sizeof(LSL)); tmp -&gt; a = k; if(SL[p] == 0) { tmp -&gt; next = 0; SL[p] = tmp; } else { tmp -&gt; next = SL[p]; SL[p] = tmp; } } } void Find_All_Arc_SL() { int i; LSL *tmp; for(i=0;i&lt;n;i++) { tmp = SL[i]; while(tmp != 0) { //printf("I find arc %d -&gt; %d \n", i, tmp-&gt;a); tmp = tmp -&gt; next; } } } /** ** CALCULATE TIME! **/ void start_timer() { freq = 0; start = 0; end = 0; diff = 0; QueryPerformanceFrequency((LARGE_INTEGER*)&amp;freq); QueryPerformanceCounter((LARGE_INTEGER*)&amp;start); } void end_timer() { QueryPerformanceCounter((LARGE_INTEGER*)&amp;end); diff = ((end - start) * 1000) / freq; } int main(int argc, char *argv[]) { Create_SL(); start_timer(); Find_All_Arc_SL(); end_timer(); printf("Find_All_Arc_SL SEARCHING ALL ARC TOOK %d \n",diff); Create_AL(); start_timer(); Find_All_Arc_AL(); end_timer(); printf("Find_All_Arc_AL SEARCHING ALL ARC TOOK %d \n",diff); system("PAUSE"); return 0; } </code></pre>
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    1. PTQuestion
    1. USDomiik
    1. USDomiik
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    1. PO
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    2. PO
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    3. PO
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    1. COSomething tells me you're measuring it wrong. Either different data, different access patterns, different warmup strategies or the wrong stopwatch methods. Show more code!
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      1. POShould be slower, but is faster. Why?
      1. USBlindy
    2. COI just have updated my post
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      1. POShould be slower, but is faster. Why?
      1. USDomiik
 

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