Problems related to calculation/cin.getline();

[Steven SPF]

Hi experts,I want to ask is there any mistakes of my calculation part?
(cin>>night; and cout<<roomfees;). This is because when I input the number of nights, the output produced doesn't match with the formula I've created.
Another problem is that why my code (cin>>name; , cin.getline();) the output will miss the first letter of what I input? Thanks in advance

#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>
#include <cstdlib>
#include <vector>
#include <cmath>
#include <ctime>
#include <windows.h>

using namespace std;

struct customer
{
    char name[100];
    string ic;
    string email;
    int roomtype;
    int night;
    double roomfees;
    string checkindate;


void add_cus();

void view_all();

};

void menu()
{

system("cls");
cout<<"======================================\n";
cout<<"     1) Add Customer Record  \n";
cout<<"     2) Edit Customer Record\n";
cout<<"     3) Delete Customer Record\n";
cout<<"     4) View All Customer Record\n";
cout<<"     5) Search Customer Record\n";
cout<<"     6) Save Customer File\n";
cout<<"     7) Exit Program\n";
cout<<"======================================\n";
cout<<"Please select an option : ";
}

void room()
{
    system("cls");
    cout<<"Please choose a room: \n"
        <<"==============================\n"
        <<"   1.) Single Room(single)\n"
        <<"       Price: RM30 per night\n"
        <<"   2.) Deluxe Room\n"
        <<"       Price: RM50 per night\n"
        <<"   3.) Double Room\n"
        <<"       Price: RM80 per night\n"
        <<"==============================\n";
}

void time_date(){

   time_t now = time(0);// current date/time based on current system
   char* dt = ctime(&now);

   cout << "Check in time: " << dt << endl;
}

void exit(){
    string msg = "Thanks for using our program.";
    system("color 1A");
   for(int i=0; i<msg.length(); i++){
      cout << msg[i] ;
      cout<<"\a";

      Sleep(250);
   }
   Sleep(250);
}

void customer::add_cus()
{
    cout<<"Customer name: ";
    cin>>name[100];
    cin.getline(name,100);
    cout<<endl;
    cout<<"IC: ";
while (!(cin >> ic) )       // get the input and check it was ok
    {
        cout<<"Invalid input. Please insert integer numbers.\n"
            <<"IC: ";
        cin.clear();            // reset flags
        cin.ignore(1000, '\n'); // empty input buffer
    }
    cout<<endl;
    cout<< "Customer Email address: ";
    cin>>email;
    cout<<endl;
    room();
    do{
    cout<<"Customer's room type choice: ";
    cin>>roomtype;
    if(roomtype == 1 )
        roomfees = night * 30;
    else if(roomtype == 2)
        roomfees = night * 50;
    else if(roomtype == 3)
        roomfees = night * 80;
    else
        cout<<"Invalid input. Please choose a room type from 1-3."<<endl;
    }while(roomtype > 3);
    cout<<endl;
    cout<<"Number of night(s): ";
    while(!(cin>>night))
    {
        cout<<"Invalid input. Please insert an integer.\n"
            <<"Number of night(s): ";
        cin.clear();
        cin.ignore(1000,'\n');
    }
    cout<<endl;
    time_date();
    cout<<endl;

}

void customer::view_all()
{
    {
    cout<< "Name:"<< name << endl;
    cout<< "IC: "<< ic << endl;
    cout<< "Email address: "<<email << endl;
    cout<< "Room type: "<<roomtype<< endl;
    cout<< "Number of night(s): "<<night<< endl;
    cout<< "Room Fees: "<<roomfees<< endl;
    time_date();
    }
}

int main()
{
    string option;//choice
    bool check;
    customer obj;//object
    int customerNo=0,z=0;//initiate
    vector<int>input;
    vector<customer>obj2;
    ifstream data;
    char set;

    data.open("CustRecord.txt",ios::in);//txt files

    if(data.is_open())//if file found

{

    int size1,read1;
    string read2;
    char read3;
    data>>read1;
    size1=read1;
    for(int r=0; r<size1;r++){
    data>>read1;
    input.push_back(read1);z++;}//pushback at last line



    for(int r=0; r<size1;r++){
    data>>read3;obj.name[100]=read3;
    data>>read2;obj.ic=read1;
    data>>read2;obj.email=read2;
    data>>read2;obj.roomtype=read1;
    data>>read2;obj.checkindate=read2;
    obj2.push_back(obj);
    }
};


do{
    menu();
    cin>>option;

if(option=="1")
{
    system("cls");
    obj.add_cus();
    obj2.push_back(obj);
    if(z>0){customerNo=input[z-1];}++customerNo;
    input.push_back(customerNo);
    system("pause");
    check=false;
}

else if(option=="2")
{
    system("cls");
    if(input.size()>0){
    int found =-1,value;
    while (cout <<"Customer No. ( refer at View All ): " && !(cin >> value))

    {
    cin.clear();
    cin.ignore();
    }cin.ignore();

    int arraySize = sizeof(input)/sizeof(int);
    int i=0;

    while(found ==-1 &&i<arraySize){
       if (input[i] ==value)
            found =i;
       i++;}
       if(found>=0){
       obj2[found].add_cus();
       }
    }else cout <<"No customer record available\n";
    system("pause");//pause
    check=false;
}

else if(option=="3")
{
    system("cls");
    if(input.size()>0){
    int b=0,ans;
    for(unsigned int i=0;i<obj2.size();i++){
    cout<<"\n";
    cout<<"Index :"<<b+1<<endl;
    obj2[i].view_all();b++;}
    while ( cout <<"Which customer record do you want to delete: " && !(cin >> ans))
            {
            cin.clear();
            cin.ignore();
            }
            cin.ignore();
           if(ans<=b&&ans>0){
            for (int j=ans-1;j<obj2.size()-1;j++){
            obj2[j].name[100]=obj2[j+1].name[100];
            obj2[j].ic=obj2[j+1].ic;
            input[j]=input[j+1];

           }
           obj2.pop_back();
           input.pop_back();//remove last

           }
    }
    else cout<<"No customer records available\n";
    system("pause");
    check=false;
}

else if(option=="4")//view all
{
    system("cls");
    if(input.size()>0){
        for(int i=0;i<obj2.size();i++)
        {
            cout<<"\nCustomer : "<<input[i]<<endl;
            obj2[i].view_all();
        }cout<<endl<<endl;
      }
        else cout <<"No customer records available\n";
    system("pause");
    check=false;
}

else if(option=="5")//search
{
    system("cls");
    if(input.size()>0){
    int found =-1,value;
    while (cout <<"Customer No. ( refer at View All ): " && !(cin >> value))

    {
    cin.clear();
    cin.ignore();
    }cin.ignore();

    int arraySize = sizeof(input)/sizeof(int);
    int i=0;

    while(found ==-1 &&i<arraySize){
       if (input[i] ==value)
            found =i;//i'th position
       i++;}
       if(found>=0){obj2[found].view_all();}
           }
else cout <<"No customer records available\n";
           system("pause");
            check=false;
}

else if(option=="6")
{
    ofstream data;
    data.open("CustRecord.txt",ios::out);
    if(data.is_open()){
    data<<input.size()<<endl;
    for(int r=0; r<input.size();r++){
    data<<input[r]<<endl;}

    for(int r=0; r<input.size();r++){
    data<<"\n";

    data<<"Customer Name: "<<obj2[r].name<<endl;
    data<<"Customer IC: "<<obj2[r].ic<<endl;
    data<<"Customer Email address: "<<obj2[r].email<<endl;
    data<<"Customer Room Type Choice: "<<obj2[r].roomtype<<endl;
    data<<"Customer Room Fees: "<<obj2[r].roomfees<<endl;
    data<<"Number of Night: "<<obj2[r].night<<endl;
    }
    data.close();
    check=false;
    system("pause");
    }
}

else if(option=="7")//exit the program
{
    string quit;
    system("cls");
    cout<<"Are you sure you want exit the program?\n"
        <<"Press Y to exit.\n";
    cin>>quit;
    if(quit != "Y" && quit != "y")
    {
        system("cls");
        check=false;
    }

    else
    {
        system("cls");
        exit();
        return 0;
    }
}

else
{
    cout <<"Invalid selection. Please enter a valid selection (1-7)\n";
    system("pause");
    check=false;
}

}while(!check);
return  0;
}//end of project

[jlb]

I have a couple of questions about the following snippet:

   cout<<"Customer name: ";
    cin>>name[100];
    cin.getline(name,100);

First why are you trying to have the user enter the name twice, first with the extraction operator then with getline()?

Second why is name an array of char instead of a std::string?

Third do you realize that in the code above you are accessing your array out of bounds when you try to extract a single character into the 100^th element? Remember valid array indexes are 0 to size - 1, 100 is one past the end of the array. Do you realize that that line is actually retrieving a single character? To retrieve C-string you wouldn't use the [100].

You may want to re-examine your code, making sure every beginning brace { has a matching ending brace } and there are no mismatches.

Because of your inconsistent indentation it's hard to read the code so this is all I'll comment about for now, except to notice you have a function named exit(), you shouldn't use this name for your function, there is already a standard function with that name.

[Steven SPF]

Thanks for the reply anyway.
For the first question, I don't really understand what do you mean by "user enter the name twice". Is that "cin>>name;" and "cin.getline(name,100)" having the same function?

Secondly, I used char instead of a std::string because I searched an example from the Internet and it does work. However, the problem happened as what I mentioned in the question.

The third one, I don't really understand about the statement you made since I'm pretty weak in the concept of array. :(

[jlb]

For the first question, I don't really understand what do you mean by "user enter the name twice". Is that "cin>>name;" and "cin.getline(name,100)" having the same function?

Yes both the extraction operator>> and getline() try to retrieve a value from the user to place into a variable, name in this case. You only need one of these lines, I suggest you stick with the getline().

Secondly, I used char instead of a std::string because I searched an example from the Internet and it does work.

What didn't work? You appear to be using std::string elsewhere in your program so what exactly doesn't work in this instance?

The third one, I don't really understand about the statement you made since I'm pretty weak in the concept of array.

This is one of the reasons I asked why you were using a C-string in this instance instead of the std::string you are using elsewhere in your program. You don't seem to understand the difference between an array of char and a single char. When you defined your array you set the maximum size of this array, in this case 100:

char name[100]; // Define an array of char named name.

Now when you tried to use this array in your program you are trying to access one character because you used a number inside brackets.

    cin>>name[100];

Look at the other places in your program, do you use these brackets? Also as I have already stated arrays in C++ start at 0 and end at size - 1. Since the size of your array is 100, trying to access the array with an index greater than 99 would be accessing the array out of bounds.