Program only prints out the first two lines of my code, and ignores the rest entirely-CodePudding

So the problem I am facing here is that, the program runs only the first two lines of the code and entirely ignores the rest. I have tried rewriting it, I have also searched the internet for solution, but I found nothing and the problem continues to persist.

#include <iostream>
using namespace std;

struct customer{
    char A_ID[10];
    char pin[4];
    char amount[20];
    int input;
    int csnt;
}c;

int main()
{
 struct customer *p;
//  Welcome Note
 cout<<"Welcome to Absa,insert your card and enter you pin: "<<endl;
 cin.getline(c.pin,sizeof(c.pin));
 
//  Transaction Menu
 cout<<"1. Transfer"<<endl
 <<"2. Deposit"<<endl
 <<"3. Change pin"<<endl
 <<"4. Account Balance"<<endl;
 cin>>c.input;
 
//  Transaction Process
switch(c.input){
    case 1:
    cout<<"Enter amount: "<<endl;
    cin>>c.amount[9];
    cout<<"Enter recipient Account number: "<<endl;
    cin>>c.A_ID[10];
    cout<<"Payment of GHc "<<c.amount<<"made to "<<c.A_ID<<endl;
    cout<<"Enter 1 to confirm or 2 to cancel: "<<endl;
    cin>>c.csnt;
    if(c.csnt==1){
        cout<<"Transfer successful, thank you for Banking with Absa."<<endl;
    }
    else if(c.csnt==2){
        cout<<"Transfer cancelled, thank you for Banking with Absa."<<endl;
    }
}



return 0;

}

CodePudding user response：

Your p variable has not been initialized yet:

struct costumer *p;

That means it does not point to an instantiated object of type costumer. So this is how you can create an object on the heap:

std::unique_ptr<costumer> ptr { std::make_unique<costumer>{ } };

ptr will handle the deletion of the costomer object for you.

But there is really no need for you to use a pointer to costumer in this case. Just create it on the stack:

costumer cost; // here cost is stored on the stack so no need to deal with pointers
               // also struct keyword is not required here (in C  )

Then use the . operator to access its members like this:

std::cin >> cost.input;

Note: I don't understand what exactly you're trying to do here:

std::cin >>p->pin[4];

So my guess is that you are trying to assign a 4 digit number to pin array. This is not valid. But you may do this instead:

struct costumer {
...
    char pin[4]; // use a char array
...
}

// get exactly 4 `char`s from the user and store in `pin`
std::cin.getline( cost.pin, sizeof(cost.pin) );

// or like this
std::string temp_pin;
std::getline( std::cin, temp_pin );

if (temp_pin.size() == 4)
{ // for example print success message;
    std::strncpy( cost.pin, temp_pin.data(), sizeof(cost.pin) );
}
else
{ // repeat the input process }

Also, you seem to mix C and C for no particular reason. Try to use only one of them to prevent any problems that might arise due to the different behaviors of C and C functions. Use std::cout or std::format (with C 20).