my CLL program in C++ wont stop looping! why? [closed] - c++

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I wrote a program using single CLL in order to have the following output:
Main Menu
Create Books CLL
Add book
Search (by Book Name)
Delete Author
Enter your Choice: 1
Enter Book ID: 11223344
Enter Book Name: Programming C++
Enter Author’s Name: Jhone
Node Created
But when i enter the first choice i will enter the book id, book name and then it will start looping without stop! What's wrong with my program?
#include<iostream>
#include<cstdio>
#include<cstdlib>
using namespace std;
struct node
{
int bid;
char book,author;
struct node *next;
}*last;
class circular_llist
{
public:
void create_node(int id,char bname,char aname);
void add_begin(int id,char bname,char aname);
void delete_element(char author);
void search_element(char name);
void display_list();
circular_llist()
{
last = NULL;
}
};
int main()
{
int choice, bid, position;
char name,author;
circular_llist cl;
while (1)
{
cout<<endl<<"Main Menu:"<<endl;
cout<<"1.Create Node"<<endl;
cout<<"2.Add at beginning"<<endl;
cout<<"3.Delete"<<endl;
cout<<"4.Search"<<endl;
cout<<"5.Display"<<endl;
cout<<"6.Quit"<<endl;
cout<<"Enter your choice : ";
cin>>choice;
switch(choice)
{
case 1:
cout<<"Enter the Book ID: ";
cin>>bid;
cout<<"Enter the Book Name: ";
cin>>name;
cout<<"Enter the Book Author: ";
cin>>author;
cl.create_node(bid,name,author);
cout<<endl;
break;
case 2:
cout<<"Enter the Book ID: ";
cin>>bid;
cout<<"Enter the Book Name: ";
cin>>name;
cout<<"Enter the Book Author: ";
cin>>author;
cl.add_begin(bid,name,author);
cout<<endl;
break;
case 3:
if (last == NULL)
{
cout<<"List is empty, nothing to delete"<<endl;
break;
}
cout<<"Enter the Author name for deletion: ";
cin>>author;
cl.delete_element(author);
cout<<endl;
break;
case 4:
if (last == NULL)
{
cout<<"List Empty!! Can't search"<<endl;
break;
}
cout<<"Enter Book Name: ";
cin>>name;
cl.search_element(name);
cout<<endl;
break;
case 5:
cl.display_list();
break;
case 6:
exit(1);
}
}
return 0;
}
void circular_llist::create_node(int id,char bname,char aname)
{
struct node *temp;
temp = new(struct node);
temp->bid = id;
temp->book = bname;
temp->author = aname;
if (last == NULL)
{
last = temp;
temp->next = last;
}
else
{
temp->next = last->next;
last->next = temp;
last = temp;
}
}
void circular_llist::add_begin(int id,char bname,char aname)
{
if (last == NULL)
{
cout<<"First Create the list."<<endl;
return;
}
struct node *temp;
temp = new(struct node);
temp->bid = id;
temp->book = bname;
temp->author = aname;
temp->next = last->next;
last->next = temp;
}
void circular_llist::delete_element(char author)
{
struct node *temp, *s;
s = last->next;
if (last->next == last && last->author == author)
{
temp = last;
last = NULL;
free(temp);
return;
}
if (s->author == author) /*First Element Deletion*/
{
temp = s;
last->next = s->next;
free(temp);
return;
}
while (s->next != last)
{
/*Deletion of Element in between*/
if (s->next->author == author)
{
temp = s->next;
s->next = temp->next;
free(temp);
cout<<"Element "<<author;
cout<<" deleted from the list"<<endl;
return;
}
s = s->next;
}
if (s->next->author == author)
{
temp = s->next;
s->next = last->next;
free(temp);
last = s;
return;
}
cout<<"Element "<<author<<" not found in the list"<<endl;
}
void circular_llist::search_element(char name)
{
struct node *s;
int counter = 0;
s = last->next;
while (s != last)
{
counter++;
if (s->book == name)
{
cout<<"Element "<<name;
cout<<" found at position "<<counter<<endl;
return;
}
s = s->next;
}
if (s->book == name)
{
counter++;
cout<<"Element "<<name;
cout<<" found at position "<<counter<<endl;
return;
}
cout<<"Element "<<name<<" not found in the list"<<endl;
}
void circular_llist::display_list()
{
struct node *s;
if (last == NULL)
{
cout<<"List is empty, nothing to display"<<endl;
return;
}
s = last->next;
cout<<"Books List: "<<endl;
while (s != last)
{
cout<<s->bid<<"\n"<<s->book<<"\n"<<s->author<<"\n"<<endl;
s = s->next;
}
cout<<s->bid<<"\n"<<s->book<<"\n"<<s->author<<"\n"<<endl;
}

Answer 1

When you read single characters (like you do with name and author) you really read only single character. And you enter multiple characters for those fields, meaning that the first input (to name) will read the fist character of the name, and the second input (to author) will read the second character of the name. That will leave quite a few characters in the input buffer, and attempting to read anything but characters or strings will fail, but you don't check for these failures so you end up with just looping over and over again trying to read e.g. a number and failing.
Simplest solution? Begin with using std::string for strings, and continue with reading multiple-word entries using std::getline.

Answer 2

The problem is how you input author and book name, e.g., cin>>name. This reads only the first word from the input and the rest of the name (if it has spaces) is left in the input buffer. Next you try to read the menu choice number and it will fail because the next character in the buffer is the first character of the second word of the name of the book, or such. I suggest that you replace your cin >> name with std::getline.
UPDATE
Oh! I have missed that you actually input only a single character...