Question

Can someone help me with my code? This is not actually my code but is a modified code from the internet. I need to make it work. Can someone point out where the problems are?

Thanks.

Answer 1

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

FILE *filename;

typedef struct student_record{
char firstname[255], middlename[255], lastname[255], course[255], email[255], contactnum[255], studentnum[255];
struct student_record *next;
}studentdirectory;

studentdirectory *start, *last;

studentdirectory *e;

// MENU ************************************************************************************************************

void menu(void)
{
printf("\n********************************************\n");
printf(" MENU \n");
printf("********************************************\n\n");
printf(" [1] Add new Record \n");
printf(" [2] Delete a Record \n");
printf(" [3] Search for a Record \n");
printf(" [4] Display all Records \n");
printf(" [5] Save to a File \n");
printf(" [6] Exit \n");
printf("\n********************************************\n");
}

// ADD A RECORD *****************************************************************************************************

void add_new_record(studentdirectory *f){

f = (studentdirectory *)malloc(sizeof(studentdirectory));

printf("\nINPUT STUDENT INFORMATION:\n");

printf("\n\tInput student's last name: ");
getchar();
scanf("%*c%[^\n]",f->lastname);

printf("\n\tInput student's first name: ");
getchar();
scanf("%*c%[^\n]",f->firstname);

printf("\n\tInput student's middle name: ");
getchar();
scanf("%*c%[^\n]",f->middlename);

printf("\n\tInput %s %s's student number: ",f->firstname,f->lastname);
getchar();
scanf("%*c%[^\n]",f->studentnum);

printf("\n\tInput %s %s's course: ",f->firstname,f->lastname);
getchar();
scanf("%*c%[^\n]",f->course);

printf("\n\tInput %s %s's contact number: ",f->firstname,f->lastname);
getchar();
scanf("%*c%[^\n]",f->contactnum);

printf("\n\tInput %s %s's email address: ",f->firstname,f->lastname);
getchar();
scanf("%*c%[^\n]",f->email);

f = f->next;

}

// DELETE A RECORD **************************************************************************************************

void delete_a_record(void){

if(start==NULL){
printf("NO RECORD TO DELETE.");
return;
}

studentdirectory *c, *d, *scan;
char name[255];

printf("\nENTER LAST NAME TO DELETE: ");

getchar();

scanf("%*c%[^\n]", name);

last->next = NULL;
c = start;
scan = start;

// IF THERE IS NO RECORD FOUND **********************************

while(scan!=NULL){

if(strcmp(name,scan->studentnum)==0){
break;
}
else{
if(scan->next==NULL){

printf("\n\nNO RECORD TO DELETE.\n\n");
free(scan);
return;

}
scan=scan->next;
}
}

// IF THERE IS A RECORD *****************************************

//IF RECORD IS AT THE BEGGINING
if(strcmp(name,start->lastname)==0){

c = start;
start = start->next;
free(c);
}

//IF RECORD IS NOT AT THE BEGINNING
else{

//IF RECORD IS AT THE END
if (strcmp(name,last->lastname)==0){

c = start;

while (c!=NULL){

if (c->next==last) //THIS FINDS THE LAST NODE IN THE LINKED LIST
break;
else
c = c->next; // IF NOT YET FOUND, THIS WILL MOVE THE TEMP POINTER TO THE NEXT NODE
}

free(c->next); //AFTER FINDING THE LAST NODE, THIS WILL FREE THAT NODE
last = c; //THEN THE 2ND TO THE LAST NODE WILL BE THE LAST NODE
last->next = NULL;
}

//IF RECORD IS AT THE MIDDLE
else{

last->next=NULL;
c = start; //THIS WILL START FINDING THE RECORD IN THE MIDDLE

while(strcmp(name,c->lastname)!=0){
c = c->next;
}

d = c; // AFTER FINDING THE RECORD TO DELETE, ANOTHER TEMP POINTER IS ASSIGNED
c = c->next; // MOVE THE FIRST TEMPORARY POINTER TO THE NEXT NODE
free(d); // FREE THE 2ND POINTER

}

}
printf("\n\nRECORD DELETED.\n\n");
}

// SEARCH FOR A RECORD **********************************************************************************************

void search_for_a_record(void){

studentdirectory *i;

char name[255];
int indicator = 0;

i = start;
last->next = NULL;

printf("\nENTER LASTNAME TO SEARCH (CASE SENSITIVE): \n");

getchar();

scanf("%[^\n]s",name);

while(i!=NULL){
if (strcmp(name,i->lastname)==0){

printf("SEARCH RESULTS:\n");
printf("\n\tNAME: %s, %s %s", i->lastname,i->firstname,i->middlename);
printf("\n\tSTUDENT NO: %s", i->studentnum);
printf("\n\tCOURSE: %s",i->course);
printf("\n\tCONTACT #: %s",i->contactnum);
printf("\n\tE-MAIL ADDRESS: %s",i->email);

indicator++;
}
i = i->next;
}

if(indicator==0){
printf("SEARCH RESULTS:\n");
printf("\nNO MATCHES FOUND.\n");
}

}

// DISPLAY ALL RECORDS **********************************************************************************************

void display_all_records(void){

studentdirectory *b;

b = start;
last->next=NULL;

while (b!=last->next){

printf("\n*********************************************\n\n");

printf("Lastname: %s\n", b->lastname);
printf("Firstname: %s\n", b->firstname);
printf("Middlename: %s\n", b->middlename);
printf("Student number: %s\n", b->studentnum);
printf("Course: %s\n", b->course);
printf("Contact Number: %s\n", b->contactnum);
printf("E-mail: %s\n", b->email);

b = b->next;
}
}

// SAVE THE RECORD **************************************************************************************************

void save_to_a_file(void){

studentdirectory *a;

a = start; // PUT TEMPORARY POINTER A TO START
last->next=NULL;

filename = fopen("Directory.txt","w+"); // OPEN THE FILE

while(a!=NULL){ // LINKED LIST WILL CONTINUE TO BE SAVED TO THE FILE UNTIL END OF LINKED LIST IS REACHED

fprintf(filename,"%s",a->firstname);
fprintf(filename,"%s",a->middlename);
fprintf(filename,"%s",a->lastname);
fprintf(filename,"%s",a->studentnum);
fprintf(filename,"%s",a->course);
fprintf(filename,"%s",a->contactnum);
fprintf(filename,"%s",a->email);

a = a->next;
}

fclose(filename); // CLOSE THE FILE
}

// START OF MAIN ****************************************************************************************************

main(){

int choice;

studentdirectory *current;

current = (studentdirectory *)malloc(sizeof(studentdirectory));

start=NULL;
last=NULL;

filename = fopen("Directory.txt","r");

if(filename!=NULL){

while(feof(filename)==0){
fgets(current->firstname,255,filename);
fgets(current->middlename,255,filename);
fgets(current->lastname,255,filename);
fgets(current->studentnum,255,filename);
fgets(current->course,255,filename);
fgets(current->contactnum,255,filename);
fgets(current->email,255,filename);

if(start==NULL){
start = current;
last = current;
start->next = last;
}
else{
last->next = current;
last = current;
}
}
}

// *************************************START OF SHOWN CONTENTS AT CONSOLE.*************************************

e = start;

do{

menu();
printf("\nYour choice: ");
scanf("%d", &choice);

switch(choice){

case 1: add_new_record(e);
break;

case 2: if(start!=NULL)
delete_a_record();
else
printf("No records to delete.\n");
break;

case 3: if(start!=NULL)
search_for_a_record();
else
printf("No records to search.\n");
break;

case 4: if(start!=NULL)
display_all_records();
else
printf("No records to display.\n");
break;

case 5: save_to_a_file();
printf("The record has been saved.\n");
break;

case 6: break;

default:printf("Choice not found. Please select a number from the list above only.");
break;

}

}while(choice!=6);

}

Answer 2

please use sites like the following to paste your code.:
http://pastebin.com/
http://codeviewer.org/upload

gl!:)