assignment_2

#include <bits/stdc++.h>

using namespace std;

struct node
{
    int x, y;
    node *next;
};
node *head = NULL;

void AddFirst(int x, int y)
{
    node *newnode = (node *)malloc(sizeof(node));
    newnode->x = x;
    newnode->y = y;
    newnode->next = head;
    head = newnode;
}

int DelFirst()
{
    if (head == NULL)
        return -1;
    node *temp = head->next;
    free(head);
    head = temp;
    return 0;
}

int Del(int x, int y)
{
    node *temp = head;
    node *prev = temp;
    while (temp != NULL)
    {
        if (temp->x == x && temp->y == y)
        {
            if (temp != head)
            {
                prev->next = temp->next;
                free(temp);
            }
            else
            {
                prev = temp->next;
                free(temp);
                head = prev;
            }

            return 0;
        }
        prev = temp;
        temp = temp->next;
    }
    return -1;
}

int Search(float d)
{
    node *temp = head;
    int count = 0;
    while (temp != NULL)
    {
        if (temp->x * temp->x + temp->y * temp->y <= d * d)
        {
            count++;
            // cout << "(" << temp->x << "," << temp->y << ") ";
        }
        temp = temp->next;
    }
    return count;
}

int Search(int x, int y)
{
    node *temp = head;
    int count = 0;
    while (temp != NULL)
    {
        if (temp->x == x && temp->y == y)
        {
            count++;
        }
        temp = temp->next;
    }
    return count;
}

int Length()
{
    node *temp = head;
    int count = 0;
    while (temp != NULL)
    {
        count++;
        temp = temp->next;
    }
    return count;
}

int main()
{
    int t;
    cin >> t;
    while (t--)
    {
        int c;
        cin >> c;
        int x, y;
        float d;
        int al;
        switch (c)
        {
        case 1:
            cin >> x >> y;
            AddFirst(x, y);
            break;
        case 2:
            if (DelFirst() == -1)
                cout << -1 << endl;
            break;
        case 3:
            cin >> x >> y;
            if (Del(x,y) == -1)
                cout << -1 << endl;
            break;
        case 4:
            cin >> d;
            al = Search(d);
            if (al == 0)
                cout << -1;
            else
            {
                cout<<al;
            }
            cout << endl;
            break;
        case 5:
            cin >> x >> y;
            al = Search(x, y);
            if (al == 0)
                cout << "False";
            else
                cout << "True";
            cout << endl;
            break;
        case 6:
            cout << Length() << endl;
            break;
        default:
            break;
        }
    }
}