LT.c

// Start at subject listItem and traverse the key as an association to a new listItem // - key is also a listItem reference and its binary address is used as the traversal path // - subject and key (all list-item references are ints starting at item 0) // - if key is 0 the subject is returned unchanged, key 1 and 2 are the two single-iteration traversals item listTraverse(item subject, item key) { if (key++ > 0) { int i,j; for (i = 1; i <= key >> 1; i <<= 1) { j = subject * 3; if (key & i) j++; subject = space[j]; if (subject) space[j]; else space[j] = listInsert(); } } return subject; }