tyle="color: #b22222;">Second pass: Fill in the data structures</span>
      ncomms = 1
      c =&gt; comms(ncomms)
      io = 1
      c%src = p1(io)
      c%dst = p2(io)
      c%i1  = isrc(io)
      c%i2  = idst(io)
      c%nitems = 1
      <span style="color: #a020f0;">do</span> io = 2, norbs
         <span style="color: #a020f0;">if</span> ((p1(io) /= p1(io-1)) <span style="color: #a020f0;">.or.</span> (p2(io) /= p2(io-1))) <span style="color: #a020f0;">then</span>
            <span style="color: #b22222