Ошибка при удалении элемента из динамической памяти

#include<iostream>
#include<time.h>
using namespace std;
 
struct car {
    char brend[30];
    char model[30];
    char number[30];
    char color[30];
    int year;
    int price;
};
 
struct user {
    char name[50];
    char surname[50];
    char fathersname[50];
    char car[50];
    short firstday;
    short firstmonth;
    short lastday;
    short lastmonth;
};
void show_cars(car cars);
void show_users(user users);
car* addcar(car*& cars, int& size);
user* adduser(user*& users, int& size);
void menu();
void choose(car* cars, user* users, int& size, int&size1);
void carsearch(car cars[], int size);
void contractsearch(user users[], int size1);
void backmenu();
int monthdays(int month);
void carsearch_brend(car* cars, int& size);
void carsearch_price(car* cars, int& size);
void carsearch_number(car* cars, int& size);
void carsearch_color(car* cars, int& size);
void carsearch_year(car* cars, int& size);
void contractsearch_name(user users[], int size1);
void contractsearch_surname(user users[], int size1);
void contractsearch_fathersname(user users[], int size1);
car* dellcar(car*& cars, int& size);
user* delluser(user*& users, int& size1);
void dellall(car*& cars, user*& users, int& size, int& size1);
void debt(user* users, int& size1);
 
int main() {
    int size = 20;
    int* ptr_size = new int[size];
    car* cars = new car[size]{
        { "Toyota", "Prado", "90-JM-122", "White", 2019, 200},
        {"Toyota", "Prius", "90-JM-250", "Red", 2017, 60},
        {"Toyota", "Rav4", "90-JM-100", "Black", 2022, 200},
        {"Toyota", "Camry", "90-JM-155", "Green", 2014, 150},
        {"Toyota", "Corolla", "90-JM-145", "Purple", 2006, 50},
        {"BMW", "X4", "96-JM-096", "Black", 2016, 300},
        {"BMW", "X5", "96-JM-010", "White", 2006, 150},
        {"BMW", "X6", "96-JM-096", "Blue", 2022, 550},
        {"Chevrolet", "Malibu", "91-JM-556","Yellow", 2016, 70},
        {"Dodge", "Challenger", "92-JM-298", "Blue", 2019, 350},
        {"Ferrari", "Portofino", "99-JM-099", "Red", 2017, 3000},
        {"Ferrari", "California", "99-JM-199", "Red", 2014, 2850},
        {"Audi", "R8", "98-JM-009", "Grey", 2010, 1450},
        {"Hundai", "Elantra", "95-JM-378", "Yellow", 2021, 250},
        {"Hundai", "Sonata", "95-JM-561", "Brown", 2015, 120},
        {"Honda", "CR-V", "95-JM-567", "Violet", 2000, 50},
        {"Kia", "Rio", "93-JM-019", "Green", 2006, 60},
        {"Mersedes", "E-220", "97-JM-119", "Black", 2011, 120},
        {"Nissan", "Sunny", "92-JM-666", "Purple", 2014, 100},
        {"Opel", "Astra", "94-JM-789", "Grey", 2015, 80} 
    };
    int size1 = 10;
    int* ptr_size1 = new int[size1];
    user* users = new user[size1]{
        {"Jala", "Mukhamedova", "Mirza", "Prado", 20, 4, 25, 4},
        {"Oguz", "Mustayev", "Vugar", "Prius", 15, 5, 25, 5},
        {"Gulnara", "Mukhamedova", "Mahmud", "Portofino", 5, 3, 25, 3},
        {"Ali", "Abdullayev", "Heydar", "California", 20, 4, 25, 4},
        {"Aygun", "Mukhtarova", "Mamed", "Sunny", 7, 4, 10, 4},
        {"Baloglan", "Balabanov", "Gelemder", "Malibu", 9, 8, 19, 9},
        {"Abbas", "Eyvazov", "Aliyar", "CR-V", 3, 4, 23, 4},
        {"Cahangir", "Zeynalov", "Elshen", "Astra", 11, 2, 20, 2},
        {"Gunay", "Aliyeva", "Arzu", "Elantra", 17, 5, 20, 5},
        {"Aliyar", "Hesenov", "Hamid", "E-220", 13, 2, 27, 2},
    };
 
    menu();
    choose(cars, users, size, size1);
 
}
 
 
 
void show_cars(car cars){
    cout << "Brend: \t" << cars.brend << endl;
    cout << "Model: \t\t" << cars.model << endl;
    cout << "Number:\t\t" << cars.number << endl;
    cout << "Color:\t\t" << cars.color << endl;
    cout << "Year:\t\t" << cars.year << endl;
    cout << "Price(in manats):" << cars.price << endl;
    cout << "____________________________________" << endl;
}
void show_users(user users) {
    cout << "Name:\t\t" << users.name << endl;
    cout << "Surname:\t" << users.surname << endl;
    cout << "Fathers Name: \t" << users.fathersname << endl;
    cout << "Arended Car:\t" << users.car << endl;
    cout << "Rental Date:\t" << users.firstday<<"."<<users.firstmonth << endl;
    cout << "Return Date:\t" << users.lastday<<"."<<users.lastmonth << endl;
    cout << "____________________________________" << endl;
}
void backmenu() {
    int rep;
    cout << "Back to menu?(1-Yes, 2-No): ";
    cin >> rep;
    if (rep == 1) {
        system("cls");
        menu();
    }
    else {
        system("pause");
    }
}
void menu() {
    cout << "\t\tWelcome to 'MUKHAMEDOFF`S RENT A CAR' company" << endl;
    cout << "1.Watch all cars" << endl;
    cout << "2.Watch all contracts" << endl;
    cout << "3.Search car" << endl;
    cout << "4.Search contract" << endl;
    cout << "5.Add car" << endl;
    cout << "6.Add contract" << endl;
    cout << "7.Customer debt" << endl;
    cout << "8.Delete contract" << endl;
    cout << "9.Delete car" << endl;
    cout << "10.Delete All" << endl;
    cout << "_____________________________" << endl;
}
int monthdays(int month) {
    switch (month)
    {
    case 1:
        return 31;
        break;
    case 2:
        return 28;
        break;
    case 3:
        return 31;
        break;
    case 4:
        return 30;
        break;
    case 5:
        return 31;
        break;
    case 6:
        return 30;
        break;
    case 7:
        return 31;
        break;
    case 8:
        return 31;
        break;
    case 9:
        return 30;
        break;
    case 10:
        return 31;
        break;
    case 11:
        return 30;
        break;
    case 12:
        return 31;
        break;
    default:
        break;
    }
}
car* addcar(car*& cars, int& size) {
    car* tmp = new car[size];
    for (int i = 0; i < size; i++) {
        tmp[i] = cars[i];
    }
 
    cout << "You are adding new car, be careful!" << endl;
    cout << "The brend: ";
    cin >> tmp[size].brend;
    cout << "The model: ";
    cin >> tmp[size].model;
    cout << "Color: ";
    cin >> tmp[size].color;
    cout << "Number: ";
    cin >> tmp[size].number;
    cout << "Year: ";
    cin >> tmp[size].year;
    cout << "Price per day(in manats): ";
    cin >> tmp[size].price;
    delete[]cars;
    size++;
    return tmp;
}
user* adduser(user*& users, int& size1) {
    user* tmp = new user[size1];
    for (int i = 0; i < size1; i++) {
        tmp[i] = users[i];
    }
 
    cout << "You are adding new contract, be careful!" << endl;
    cout << "Name: ";
    cin >> tmp[size1].name;
    cout << "Surname: ";
    cin >> tmp[size1].surname;
    cout << "Father`s name: ";
    cin >> tmp[size1].fathersname;
    cout << "Write the day and month of rental date (for example 4 12): ";
    cin >> tmp[size1].firstday >> tmp[size1].firstmonth;
    cout << "Write the day and month of return date (for example 4 12):";
    cin >> tmp[size1].lastday >> tmp[size1].lastmonth;
    delete[]users;
    size1++;
    return tmp;
}
car* dellcar(car*& cars, int& size) {
    car* tmp = new car[size];
    char fin[30];
    for (int i = 0; i < size; i++) {
        cout << cars[i].brend << " " << cars[i].model << " " << cars[i].number << endl;
    }
    cout << "You are deleting car, be careful!" << endl;
    cout << "Write the number of car(example 92-JM-092): ";
    cin >> fin;
    for (int i = 0; i < size; i++) {
        if (strcmp(fin, cars[i].number) != 0) {
            tmp[i] = cars[i];
        }
    }
    delete[]cars;
    size--;
    return tmp;
}
user* delluser(user*& users, int& size1) {
    user* tmp = new user[size1];
    char fin[30];
    char fin1[30];
    for (int i = 0; i < size1; i++) {
        cout << users[i].name << " " << users[i].surname << " " << users[i].fathersname << endl;
    }
    cout << "You are deleting a contract, be careful!" << endl;
    cout << "Write the customers name: ";
    cin >> fin;
    cout << "Write the customers surname: ";
    cin >> fin1;
    for (int i = 0; i < size1; i++) {
        if (strcmp(fin, users[i].name) != 0||strcmp(fin1, users[i].surname)!=0) {
            tmp[i] = users[i];
        }
    }
    delete[]users;
    size1--;
    return tmp;
}
//void dellall(car*& cars, user*& users, int& size, int& size1) {
//  car* tmp1 = new car  [size];
//  user* tmp2 = new user[size1];
//  delete[]cars;
//  delete[]users;
//
//}
void carsearch_brend(car* cars, int& size){
    char find[30];
    bool finded = false;
    cout << "Enter the brend: ";
    cin >> find;
    for (int i = 0; i < size; i++) {
        if (strcmp(find, cars[i].brend) == 0) {
            show_cars(cars[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void carsearch_number(car* cars, int& size) {
    char find[30];
    bool finded = false;
    cout << "Enter the number: ";
    cin >> find;
    for (int i = 0; i < size; i++) {
        if (strcmp(find, cars[i].number) == 0) {
            show_cars(cars[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void carsearch_color(car* cars, int& size) {
    char find[30];
    bool finded = false;
    cout << "Enter the color: ";
    cin >> find;
    for (int i = 0; i < size; i++) {
        if (strcmp(find, cars[i].color) == 0) {
            show_cars(cars[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void carsearch_year(car* cars, int& size) {
    int find;
    bool finded = false;
    cout << "Enter the year: ";
    cin >> find;
    for (int i = 0; i < size; i++) {
        if (find == cars[i].year) {
            show_cars(cars[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void carsearch_price(car* cars, int& size) {
    int find1, find2;
    bool finded = false;
    cout << "Enter the start and end of price(example 50 100): ";
    cin >> find1 >> find2;
    for (int i = 0; i < size; i++) {
        if (cars[i].price >= find1& cars[i].price <= find2) {
            show_cars(cars[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void carsearch(car cars[], int size) {
    system("cls");
    int item;
    cout << "1. Search by brend" << endl;
    cout << "2. Search by number" << endl;
    cout << "3. Search by color" << endl;
    cout << "4. Search by year" << endl;
    cout << "5. Search by price" << endl;
    cout << "Choose the item(1-by model...etc): " << endl;
    cin >> item;
    system("cls");
    switch (item) {
    case 1:
        carsearch_brend(cars, size);
        break;
    case 2:
        carsearch_number(cars, size);
        break;
    case 3:
        carsearch_color(cars, size);
        break;
    case 4:
        carsearch_year(cars, size);
        break;
    case 5:
        carsearch_price(cars, size);
        break;
    }
}
void contractsearch_name(user users[], int size1) {
    char find[30];
    bool finded = false;
    cout << "Enter the name: ";
    cin >> find;
    for (int i = 0; i < size1; i++) {
        if (strcmp(find, users[i].name) == 0) {
            show_users(users[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void contractsearch_surname(user users[], int size1) {
    char find[30];
    bool finded = false;
    cout << "Enter the surname: ";
    cin >> find;
    for (int i = 0; i < size1; i++) {
        if (strcmp(find, users[i].surname) == 0) {
            show_users(users[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void contractsearch_fathersname(user users[], int size1) {
    char find[30];
    bool finded = false;
    cout << "Enter the father`s name: ";
    cin >> find;
    for (int i = 0; i < size1; i++) {
        if (strcmp(find, users[i].fathersname) == 0) {
            show_users(users[i]);
            finded = true;
        }
    }
    if (finded == false) {
        cout << "There is no matches!" << endl;
    }
}
void contractsearch(user users[], int size1) {
    system("cls");
    int item;
    cout << "1. Search by name" << endl;
    cout << "2. Search by surname" << endl;
    cout << "3. Search by father`s name" << endl;
    cout << "Choose the item(1-by model...etc): " << endl;
    cin >> item;
    system("cls");
    switch (item) {
    case 1:
        contractsearch_name(users, size1);
        break;
    case 2:
        contractsearch_surname(users, size1);
        break;
    case 3:
        contractsearch_fathersname(users, size1);
        break;
    }
}
void debt(user* users, int& size1) {
    char name[30];
    char surname[30];
    int day_diff, act_day, act_month, month;
    cout << "Write the name of user:";
    cin>>name;
    cout << "Write the surname of user;";
    cin>>surname;
    cout << "Write the actual date(example 4 12 for 4th of december): ";
    cin >> act_day >> act_month;
 
    for (int i = 0; i < size1; i++) {
        if (strcmp(name, users[i].name)==0 && strcmp(surname, users[i].surname)==0) {
            month = monthdays(users[i].firstmonth);
        }
    }
}
void choose(car* cars, user* users, int& size, int&size1) {
    int item;
    cout << "Choose the item(1-all cars...etc): " << endl;
    cin >> item;
    system("cls");
    switch (item)
    {
    case 1:
        for (int i = 0; i < size; i++) {
            show_cars(cars[i]);
        }break;
    case 2:
        for (int i = 0; i < size1; i++) {
            show_users(users[i]);
        }break;
    case 3:
        system("cls");
        carsearch(cars, size);
        break;
 
    case 4:
        system("cls");
        contractsearch(users, size1);
        break;
    case 5:
        cars = addcar(cars, size);
        cout << "Car sucsessfully added!" << endl;
        break;
    case 6:
        users = adduser(users, size);
        cout << "Contract sucsessfully added!" << endl;
        break;
    case 7:
        break;
    case 8:
        delluser(users, size1);
        break;
    case 9:
        dellcar(cars, size);
        break;
    /*case 10:
        dellall(cars, users, size, size1);
        break;*/
    }
    backmenu();
    choose(cars, users, size, size1);
}

user* tmp = new user[size1+1];

int j=0;
for (int i = 0; i < size; i++) {
    if (strcmp(fin, cars[i].number) != 0) {
       tmp[j++] = cars[i];  // !!!!!!!!!!!!!!!!!!!!!!!!!
    }
}
delete[]cars;
size=j;  //  !!!!!!!!!!!!!!!!!!!!!!
return tmp;