# include <stdio.h>
# include <stdlib.h>
# include <string.h>
struct node
{
    char imie[30];
    char nazwisko[30];
    struct node* parent;
    struct node* left;
    struct node* right;
};

struct node* talloc()
{
    return ((struct node*) malloc(sizeof(struct node)));
}


struct node* dodajl(struct node* a, struct node **h)
{
    int t;
    struct node** head;
    head=h;
        if (*head!=NULL)
        if ((t=strcmp(a->imie, (*head)->imie))==0)
            t=strcmp(a->nazwisko, (*head)->nazwisko);

        while((*head)!=NULL && t!=0)
        {
            if (t>0) head=&((*head)->right);
            else head=&((*head)->left);
            if ((*head)!=NULL)
                if ((t=strcmp(a->imie, (*head)/*->next*/->imie))==0)
                    t=strcmp(a->nazwisko, (*head)/*->next*/->nazwisko);
        }

        if ((*head)!=NULL) return *head;
        else
        {
            //a->left=NULL;
            //a->right=NULL;
            *head=a;
            return *head;
        }
}

void popraw(struct node* a, struct node* b)
{
    struct node* ta;
    struct node* tb;
    struct node* tmp;

    ta=a->parent;
    tb=b->parent;

    while(ta!=NULL && tb!=NULL)
    {
        if (ta->imie[0]!='\'')
            tmp=ta;
        else
            tmp=tb;
        a->parent=tmp;
        b->parent=tmp;
        ta=ta->parent;
        tb=tb->parent;
        a=a->parent;
        b=a;
    }
    if(ta!=NULL)
    {
        b->parent=ta;
        a->parent=ta;
    }
    else if(tb!=NULL)
    {
        b->parent=tb;
        a->parent=tb;
    } else
    {
        a->parent=NULL;
        //b->parent=NULL;
    }
}


void popraw2(struct node* a, struct node* ta, struct node* tb)
{
    struct node* tmp;

    while(ta!=NULL && tb!=NULL)
    {
        if (ta->imie[0]!='\'')
            tmp=ta;
        else
            tmp=tb;
        a->parent=tmp;
        ta=ta->parent;
        tb=tb->parent;
        a=a->parent;
    }
    if(ta!=NULL)
    {
        a->parent=ta;
    }
    else if(tb!=NULL)
    {
        a->parent=tb;
    } else a->parent=NULL;
}


void dodajd(char* operator, struct node* a, struct node* b)
{
    int i;
    struct node* ch;
    if (strcmp(operator,"grandparent-of")==0)
    {
        if(b->parent!=NULL)
        {
            b=b->parent;
        }
        else
        {
            ch=talloc();
            ch->parent=NULL;
            ch->imie[0]='\'';
            ch->nazwisko[0]='0';
            b->parent=ch;
            b=b->parent;
        }
        operator="parent-of";
        dodajd(operator,a,b);
    }   else

    if (strcmp(operator,"parent-of")==0)
        popraw2(b,a,b->parent);
    else

    if (strcmp(operator,"sibling-of")==0)
        popraw(a,b);
    else
    if (strcmp(operator,"grandchild-of")==0)
    {
        operator="grandparent-of";
        dodajd(operator,b,a);
    }
    else
    if (strcmp(operator,"child-of")==0)
    {
        operator="parent-of";
        dodajd(operator,b,a);
    }
    else
    if (strcmp(operator,"cousin-of")==0)
    {
        if ((a->parent)!=NULL)
        {
            a=a->parent;
        }
        else
        {
            ch=talloc();
            ch->imie[0]='\'';
            ch->nazwisko[0]='\'';
            ch->parent=NULL;
            a->parent=ch;
            a=a->parent;
        }
        if ((b->parent)!=NULL)
        {
            b=b->parent;
        }
        else
        {
            ch=talloc();
            //ch->next=NULL;

            ch->imie[0]='\'';
            ch->nazwisko[0]='\'';

            ch->parent=NULL;
            b->parent=ch;
            b=b->parent;
        }
        operator="sibling-of";
        dodajd(operator,a,b);


    }
}


znajdz(struct node* a, struct node* b)
{
    struct node* c;
    b=b->parent;
    c=b;
    a=a->parent;
    while (a!=NULL && a!=b)
    {
        b=c;
        while (b!=NULL && a!=b)
            b=b->parent;
        if (a!=b)
            a=a->parent;
    }
    if (a!=NULL)
    while(a!=NULL && a->imie[0]=='\'')
        a=a->parent;
    if (a==NULL)
        printf("NN\n");
    else
        printf("%s %s\n", a->imie, a->nazwisko);
}


int main()
{
    struct node* a;
    struct node* b;
    struct node* head;
    char* operator;

    operator=malloc(16*(sizeof(char)));
    head=NULL;
    a=talloc();
    b=talloc();

    while(scanf("%s %s %s %s %s",a->imie, a->nazwisko, operator, b->imie, b->nazwisko)!=EOF)
    {
        a->right=NULL;
        a->left=NULL;
        a->parent=NULL;
        b->parent=NULL;
        b->right=NULL;
        b->left=NULL;
        a=dodajl(a, &head);
        b=dodajl(b, &head);
        if (strcmp(operator,":")!=0)
            dodajd(operator, a, b);
        else
            znajdz(a,b);
        a=talloc();
        b=talloc();
    }
}