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some comments

Rafael Arce Nazario 5 years ago
parent
commit
db9026ac79
1 changed files with 13 additions and 1 deletions
  1. 13
    1
      Llist.cpp

+ 13
- 1
Llist.cpp View File

35
 
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 void Llist::insertAfter(Node *p, ElementType d) {
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 void Llist::insertAfter(Node *p, ElementType d) {
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   Node *n;
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   Node *n;
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+
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+  // p == NULL is interpreted as prepending
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   if (p == NULL) {
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   if (p == NULL) {
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     n = new Node(d, head);
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     n = new Node(d, head);
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     head = n;
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     head = n;
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 void Llist::printRev() const {
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 void Llist::printRev() const {
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   printRev(head); 
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   printRev(head); 
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 }
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 }
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+
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 void Llist::printRev(Node *p) const {
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 void Llist::printRev(Node *p) const {
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   if (p != NULL) {
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   if (p != NULL) {
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     printRev(p->next);
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     printRev(p->next);
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 void Llist::removeAfter(Node *cur) {
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 void Llist::removeAfter(Node *cur) {
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   Node *suc;
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   Node *suc;
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+
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+  // cur == NULL is interpreted as removing the first
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+  // node of the list
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   if (cur == NULL and head != NULL) {
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   if (cur == NULL and head != NULL) {
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     suc = head->next;
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     suc = head->next;
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     delete head;
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     delete head;
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     head = suc;
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     head = suc;
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-
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+    // in case the removed node was the only node
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     if (suc == NULL) tail = NULL;
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     if (suc == NULL) tail = NULL;
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   }
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   }
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   else if (cur->next != NULL) {
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   else if (cur->next != NULL) {
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     suc = cur->next->next;
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     suc = cur->next->next;
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     delete cur->next;
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     delete cur->next;
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     cur->next = suc;    
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     cur->next = suc;    
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+    // if the removed node was the last, update the tail pointer
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     if (suc == NULL) tail = cur;
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     if (suc == NULL) tail = cur;
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   }
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   }
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   length--;
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   length--;
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 }
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 }
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+// Assignment operator:
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+// 1. empty the list of the invoking object
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+// 2. traverse the list of the parameter appending each
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+//    node data to the invoking object
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+
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 Llist& Llist::operator=(const Llist &L) {
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 Llist& Llist::operator=(const Llist &L) {
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   if (this != &L) {
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   if (this != &L) {
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     while(head != NULL) removeAfter(NULL);
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     while(head != NULL) removeAfter(NULL);