#!/usr/bin/awk -f

# Generate topologically sorted list of manual chapters.

# Copyright (C) 1998-2018 Free Software Foundation, Inc.

# Written by Ulrich Drepper <drepper@cygnus.com>, 1998.

BEGIN {

  cnt = 0

  dnt = 0

}

{

  to[dnt] = $1

  from[dnt] = $2

  ++dnt

  all[cnt++] = $1

}

END {

  do {

    moved = 0

    for (i = 0; i < dnt; ++i) {

      for (j = 0; j < cnt; ++j) {

	if (all[j] == from[i]) {

	  for (k = j + 1; k < cnt; ++k) {

	    if (all[k] == to[i]) {

	      break;

	    }

	  }

	  if (k < cnt) {

	    for (l = k - 1; l >= j; --l) {

	      all[l + 1] = all[l]

	    }

	    all[j] = to[i]

	    break;

	  }

	}

      }

      if (j < cnt) {

	moved = 1

	break

      }

    }

  } while (moved)

  for (i = 0; i < cnt; ++i) {

    print all[i];

  }

}