title: Why is my output 5 and 0 instead of 6 and 5
body: <p>Why my code output is 5 and 0, not 6 and 5?</p>
  <p>I think I should get 6 and 5. I am a beginner.</p>
  <pre><code>#include &lt;stdio.h&gt;
  int swap(int a,int b);
  int main()
  {   int x =5;
      int y =6;
      printf(&quot;%d %d\n&quot;,x,y);
      int number[2]={swap(x,y)};
      x=number[0];
      y=number[1];
      
      printf(&quot;%d %d\n&quot;,x,y);
      return 0;
  }
  int swap(int a,int b)
  {
      return b,a;
  }
  </code></pre>