Excerpt from my Family Tree

gistfile1.cpp

/**
 * Prints all of ancestors of the given `full_name`, `level` is used
 * for indicates the level of ancestors.
 */
void FamilyLinkedList::PrintAncestors(string full_name, int level) {
    FamilyNode *person = Get(full_name);
    // base case
    if (person == NULL || full_name.compare(kNotIdentified) == 0) {
        return;
    }
    FamilyNode *node = head_;

    string prefix = "grand ";
    int i;
    // level - 1 because 1 level (grand father is not great-grand father)
    for (i = 0; i < level - 1; i++) {
        prefix = "great-" + prefix;
    }
    if (level == 0) {
        prefix = "";
    }

    // printf("L %d\n", level);
    // Only father and mother is look up based on the member variable not the
    // node in linked list.
    if (person->father().compare(kNotIdentified) != 0) {
        printf("%s, %sfather\n", person->father().c_str(), prefix.c_str());
        PrintAncestors(person->father(), level + 1);
    }
    if (person->mother().compare(kNotIdentified) != 0) {
        printf("%s, %smother\n", person->mother().c_str(), prefix.c_str());
        PrintAncestors(person->mother(), level + 1);
    }
}

/**
 * Prints all of descendants of the given `full_name`, `level` is used
 * for indicates the level of descendants.
 */
void FamilyLinkedList::PrintDescendants(string full_name, int level) {
    FamilyNode *person = Get(full_name);
    FamilyNode *node = head_;
    int counter = 0;
    string prefix = "grand ";
    int i;
    // level -1 because 1 level is grand daughter or grand son
    for (i = 0; i < level - 1; i++) {
        prefix = "great-" + prefix;
    }
    if (level == 0) {
        prefix = "";
    }

    while (node != NULL) {
        if (EqualsIgnoreCase(node->father(), full_name) ||
                EqualsIgnoreCase(node->mother(), full_name)) {
            if (EqualsIgnoreCase(node->sex(), kFemale)) {
                printf("%s, %sdaughter\n", node->full_name().c_str(),
                        prefix.c_str());
            } else {
                printf("%s, %sson\n", node->full_name().c_str(),
                        prefix.c_str());
            }
            // print descendants recursively
            PrintDescendants(node->full_name(), level + 1);
        }
        node = node->next;
    }
}

/**
 * Prints siblings of `full_name`.
 */
void FamilyLinkedList::PrintSiblings(string full_name) {
    FamilyNode *person = Get(full_name);
    FamilyNode *node = head_;
    while (node != NULL) {
        // Common father or mother
        if ((EqualsIgnoreCase(node->father(), person->father()) ||
             EqualsIgnoreCase(node->mother(), person->mother())) &&
             !EqualsIgnoreCase(node->full_name(), person->full_name())) {
            if (EqualsIgnoreCase(node->sex(), kFemale)) {
                if (node->age() == person->age()) {
                    printf("%s, sister [same age %d]\n",
                            node->full_name().c_str(),
                            person->age());
                } else if (node->age() > person->age()) {
                    printf("%s, elder sister\n",
                            node->full_name().c_str());
                } else {
                    printf("%s, younger sister\n",
                            node->full_name().c_str());
                }
            } else {
                if (node->age() == person->age()) {
                    printf("%s, brother [same age %d]\n",
                            node->full_name().c_str(),
                            person->age());
                } else if (node->age() > person->age()) {
                    printf("%s, elder brother\n",
                            node->full_name().c_str());
                } else {
                    printf("%s, younger brother\n",
                            node->full_name().c_str());
                }
            }
        }
        node = node->next;
    }
}

/**
 * Prints all of the relative of `full_name`.
 * The person full_name=`full_name` must exists in the linked list.
 */
void FamilyLinkedList::PrintRelativesOf(string full_name) {
    printf("\n%s's relatives:\n\n", full_name.c_str());
    PrintAncestors(full_name, 0);
    PrintDescendants(full_name, 0);
    PrintSiblings(full_name);
    return;
}