public static String pformat(Collection<?> c) {
if(c.size() == 0) return "[]";
StringBuilder result = new StringBuilder("[");
for(Object elem : c) {
if(c.size() != 1)
result.append("\n ");
result.append(elem);
}
if(c.size() != 1)
result.append("\n");
result.append("]");
return result.toString();
}