ProjectCars

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct Students *head = NULL;
struct Students *temp = NULL;
int i =0;

struct Students{
        char firstName[15];
        char lastName[15];
        char grade[10];
        int ID;
        double score;
        struct Students *next;
};

void text()
{
    printf("--------------------------\n");
    printf("Enter a new student\n");
    printf("Check student's info\n");
    printf("Edit student's info\n");
    printf("Exit\n");
    printf("--------------------------\n");
}

void new()
{
    if(i == 0){
    i++;
    head = malloc(sizeof(struct Students));
    if(head == NULL) perror("NEW HEAD ERROR");
    printf("Student's name : "); scanf("%s %s", head->firstName, head->lastName);
    printf("Student's grade : "); scanf("%s", head->grade);
    printf("Student's ID : "); scanf("%d", &(head->ID));
    printf("Student's score : "); scanf("%lf", &(head->score));
    head->next = NULL;

    }
    else{
    struct Students *student = malloc(sizeof(struct Students));
    if(student == NULL) perror("NEW STUDENT ERROR");

    temp = head;
    head = student;
    head->next = temp;


    printf("Student's name : "); scanf("%s %s", head->firstName, head->lastName);
    printf("Student's grade : "); scanf("%s", head->grade);
    printf("Student's ID : "); scanf("%d", &(head->ID));
    printf("Student's score : "); scanf("%lf", &(head->score));
    }
}

void check(struct Students *current, int ID)
{
    while(current != NULL){
        if(current->ID == ID){
            printf("ID : %d\n", current->ID);
            printf("Name : %s %s\n", current->firstName, current->lastName);
            printf("Grade : %s\n", current->grade);
            printf("Score : %.2lf\n", current->score);
            break;
        }
        else
            current = current->next;
    }



}
int main()
{
    int scanID = 0;
    FILE *fp = fopen("student.dat", "w");
    if(fp == NULL)
        perror("ERROR");

    printf("Welcome! Choose an action.\n");
    char *action = malloc(10*sizeof(char));
    if (action == NULL) perror("MAIN ACTION ERROR");
    text();


    while(1){
        scanf("%s", action);
        if(strcmp(action, "New")== 0){
                printf("\n");
            new();
        }
       else if(strcmp(action, "Check") == 0){
            printf("\nEnter student's ID : ");
            scanf("%d",&scanID);
            check(head, scanID);
        }
        else
        {
            while(head != NULL){
           fwrite(head, sizeof(struct Students), 1, fp);

        if(fwrite != 0)
            printf("contents to file written successfully !\n");
        else
            printf("error writing file !\n");



            head = head->next;

            }
            fclose(fp);
            return 96;

        }

         printf("\nChoose another action : ");

    }


}