Lab17B

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <math.h>
#include <io.h>
#include <stdio.h>
using namespace std;
struct car
{
    char name[100];
    int speed;
    int year;
};
void generate_arr(FILE *, int, char*);
void h_add(car, int, car *, int *);
int h_seach(int, int, car *, int *);
int main()
{
    FILE *fl;
    char * fname = "lab17.txt";
    int n, i, m,k;
    cout << "Enter hash" << endl;
    cin >> m;
    cout << "Enter amount of cars:";
    cin >> n;
    if (n > m)
    {
        cout << "hash should not be more than the amount of cars" << endl;
        system("pause");
        exit(1);
    }
    if ((fl = fopen(fname, "rb")) == NULL)
    {
        generate_arr(fl, m, fname);
    }
    k = filelength(fileno(fl)) / sizeof(int);
    int *arr = new int[k];
    fread(arr, sizeof(int), k, fl);
    car *Hash = new car[m];
    car *rac = new car[n];

    for (i = 0; i < n; i++)
    {
        cout << "Enter name of car: ";
        cin >> rac[i].name;
        cout << "Enter speed: ";
        cin >> rac[i].speed;
        cout << "Enter year: ";
        cin >> rac[i].speed;
        cout << endl;
    }
    for (i = 0; i < m; i++) Hash[i].year = -1;
    for (i = 0; i < n; i++) h_add(rac[i], m, Hash,arr);
    cout << endl;
    for (i = 0; i < m; i++) cout << "Hash[" << i << "].year " << Hash[i].year << endl;
    int key, x;
    cout << "Enter key" << endl;
    cin >> key;
    x = h_seach(key, m, Hash,arr);
    if (x == -1)cout << "No element" << endl;
    else
    {
        cout << "elment x=" << x << endl;
        cout << "name of car: " << Hash[x].name << endl;
        cout << "speed: " << Hash[x].speed << endl;
        cout << "year: " << Hash[x].year << endl;
    }
    delete[]arr;
    delete[]rac;
    delete[]Hash;
    fclose(fl);
    system("pause");
    return 0;
}
void h_add(car rac, int m, car *Hash, int *arr)
{
    int i = rac.year % m;
    int p = 0;

    if (Hash[i].year != -1)
    {
        while (Hash[i].year != -1)
        {
            p++;
            i += arr[p];
            if (i >= m)
            {
                i = 0;
                break;
            }
        }
        while (Hash[i].year != -1) i++;
    }
    Hash[i] = rac;
}
int h_seach(int inf, int m, car *Hash, int *arr)
{
    int i = inf % m;
    int p = 0;
    if (Hash[i].year == inf) return i;
    while (Hash[i].year != -1)
    {
        p++;
        i += arr[p];
        if (i >= m)
        {
            i = 0; break;
        }
        if (Hash[i].year == inf) return i;
    }
    while (Hash[i].year != -1)
    {
        if (Hash[i].year == inf) return i;
        i++;
    }
    return -1;
}
void generate_arr(FILE *fl, int m, char*fname)
{
    int r;
    srand(time_t(NULL));

    if ((fl = fopen(fname, "wb")) == NULL)
    {
        cout << "error";
        system("pause");
        exit(1);
    }
    for (int i = 0; i < m; i++)
    {
        r= rand() % 5;
        fwrite(&r, sizeof(r), 1, fl);
    }

}