HASH_2.1

#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <stddef.h>

int const a = 1;
int const b = 0;
int const p = 89;
int const m = 15;
int max = 0;
int min = 0;
int max_key = 0;
int min_key = 0;

typedef struct node{
    int value;
    int square;
    float radical;
    struct node *next;
    struct node *early;
}node;

int search_number (int key){
    int i;
    for (i = 0; i < m; i++){
        if (i==(((a*key + b)% p)% m)){
            return i;
        }
    }
    return -1;
}

void insert_node (int *A, int key){
    int i = search_number (key);
    node *tmp = (node*) malloc(sizeof(node));
    tmp->value = key;
    tmp->square = key*key;
    tmp->radical = sqrt((float)key);
    if (A[i] == 0){
        A[i] = tmp;
        tmp->next = NULL;
        tmp->early = NULL;
    }
    else{
        node *tmp2;
        tmp2 = A[i];
        A[i] = tmp;
        tmp->next = tmp2;
        tmp2->early = tmp;
    }
}

void output_list (int *A, int key){
    int j;
    j = search_number (key);
    if (!A[j]){
        printf ("no elements");
    }
    else{
        node *iter = A[j];
        while (iter != NULL){
            printf ("Value: %d\n", iter->value);
            printf ("The square root of value: %f\n", iter->radical );
            printf ("The square of value: %d\n", iter->square );
            iter = iter->next;
            printf ("\n");
        }
    }
}

int search_key (int *A, int key){
    int i, find = -1;
    i = search_number (key);
    node *iter;
    iter = A[i];
    while (iter){
        if (iter->value == key) find = 1;
        iter = iter->next;
    }
    return find;
}

int delete_node (int *A, int key){

    int i, done = -1;
    max = 0;
    max_key = 0;
    i = search_number (key);
    node *iter;
    iter = A[i];
    iter->early = NULL;
    while (1){
        if (iter->value == key){
            done = 1;
            break;
        }
        iter = iter->next;
    }
    node *temporary;
    temporary = iter;
    if ((iter->early == NULL)&&(iter->next == NULL)){ //first element and last
        A[i] = NULL;
        free (temporary);
        return done;
    }
    if ((iter->early != NULL)&&(iter->next != NULL)){ //in the middle
        node *tmp;
        tmp = iter->next;
        iter->next->early = iter->early;
        iter->early->next = tmp;
        free (temporary);
        return done;
    }
    if ((iter->early == NULL)&&(iter->next != NULL)){
        A[i] = iter->next;
        iter->next = NULL;
        free (temporary);
        return done;
    }
    if ((iter->early != NULL)&&(iter->next == NULL)){
        iter->early->next = NULL;
        free (temporary);
        return done;
    }
}

void max_list (int *A){
    node *iter;
    int i, count;
    for (i = 0; i < m; i++){
        iter = A[i];
        count = 0;
        if (iter != NULL){
            while (1){
                count ++;
                if (iter->next == NULL)
                    break;
                iter = iter->next;
            }
            if (max < count){
                max = count;
                max_key = iter->value;
            }
        }

    }
}

int main (void){
    int count = 30;
    int number, key, key2, i;
    int *A[m];

    for (i = 0; i < m; i++){
        A[i] = NULL;
    }

    FILE *mf;
    printf ("opening file :");
    mf = fopen ("C:\\Users\\Anna\\Documents\\ci\\hash.dat","r+");
    if (mf == NULL)
        printf ("error\n");
    else printf ("done\n");

    for (i = 0; i < count; i++){
        fscanf(mf, "%d %d", &number, &key);
        printf ("%d\n", key);
    //  printf ("%d\n", j);
        insert_node (A, key);
    }
    printf ("\n");

    int variety, search;
    int behavior = 1;
    while (behavior){
        printf ("Choose what u want:\n1-Add data\n2-Search key \n3-Delete key\n4-Watch on minimal, maximal, average of list\n0-If you want stop this\n");
        printf ("Your choice: ");
        scanf ("%d", &variety);
        switch (variety){
        case 1:
            count++;
            printf ("Input key, what we want insert: ");
            scanf ("%d", &key);
            insert_node (A, key);
            printf ("let's see what lye in A if key = %d\n", key);
            output_list (A, key);
            break;
        case 2:
            printf ("Input key, which we search: ");
            scanf ("%d", &key);
            search = search_key (A, key);
            if (search == -1){
                printf ("no this key in hash-table\n");
            }
            else {
                printf ("U have this key in hash-table\n");
                output_list (A, key);
            }
            break;
        case 3:
            printf ("Input key, which delete: ");
            scanf ("%d", &key2);
            search = search_key(A, key2);
            if (search == -1){
                printf ("no this key in hash-table\n");
            }
            else {
                int del;
                del = delete_node (A, key2);
                if (del == -1){
                    printf ("Error. This element wasn't deleted\n");
                }
                else {
                    count--;
                    printf ("Good job. Element was deleted\n");
                }
            }
            break;
        case 4:
            max_list (A);
        //  min_list (A);
            printf ("Max lengh of list %d, this is for this key %d\n", max, max_key);
            printf ("Min lengh of list %d, this is for this key %d\n", min, min_key);
            float average;
            average = (float)count/(float)m;
            printf ("Average lengh of list %f\n", average);
            break;
        case 0:
            behavior = 0;
            break;
        default:
            printf("Wrong input\n" );
            break;
        }
    }
    fclose (mf);
    printf ("file closed\n");
    return 0;
}