title: how to write a recursive program using c language?
body: <p>I want to write a C program that read any five int input like A B C D E</p>
  
  <p>and output </p>
  
  <pre><code>A-B, A-C, A-D, A-E
  
  B-C, B-D, B-E
  
  C-D, C-E
  
  D-E
  </code></pre>
  
  <p>The <code>-</code> is to do the minus operator, using as short code as you can.</p>
  
  <p>So I don't want to do for loop iteration.</p>
  
  <pre><code>int i,j,a[5]={'\0'};
  scanf("%d%d%d%d%d",&amp;a[0],&amp;a[1],&amp;a[2],&amp;a[3],&amp;a[4]);
  
  for(int i=0;i&lt;4;i++)
      for(int j=i+1;j&lt;5;j++)
          printf("%d\n",a[i]-a[j]);
  </code></pre>