Could not Input value many times - c++

Question

I just started C++ recently and now I encounter a problem in a very simple program. I was successful inputting part_num and part_des (both type string), but the program skipped part_price and part_quant (type int). I could not enter values for these two last variables.How do I fix this problem? Thanks
#include <iostream>
using namespace std;
int main()
{
string part_num;
string part_des;
int part_price;
int part_quant;
cout<<"Please enter the part number: ";
cin>>part_num;
cout<<"\n"<<endl;
cout<<"Please enter the part description: ";
cin>>part_des;
cout<<"\n"<<endl;
cout<<"Please enter the part price: ";
cin>>part_price;
cout<<"\n"<<endl;
cout<<"Please enter the part quantity: ";
cin>>part_quant;
cout<<"\n"<<endl;
}

Answer 1

What Happens
Please test for yourself:
#include <iostream>
#include <string>
using namespace std;
int main()
{
string my_string;
cout << "enter a string: ";
cin >> my_string;
cout << "you have entered: " << my_string << endl;
system("pause");
}
Results:
enter a string: one
you have entered: one
Press any key to continue . . .
enter a string: one two
you have entered: one
Press any key to continue . . .
Where is "two"? It remains in stream. When you try to get a number after this, this piece of text is automatically taken as your input, probably it rises an exception and your program suddenly ends.
How to Fix
Use something like getline.
#include <iostream>
#include <string>
using namespace std;
int main()
{
string my_string;
cout << "enter a string: ";
getline (cin, my_string);
cout << "you have entered: " << my_string << endl;
system("pause");
}
This will eliminate the problem you're having.
enter a string: one two
you have entered: one two
Press any key to continue . . .

Answer 2

The code works fine. ( if you don't have whitespaces in there )
#include <iostream>
using namespace std;
int main()
{
string part_num;
string part_des;
int part_price;
int part_quant;
cout<<"Please enter the part number: ";
cin>>part_num;
cout<<"\n" << part_num <<endl;
cout<<"Please enter the part description: ";
cin>>part_des;
cout<<"\n" << part_des <<endl;
cout<<"Please enter the part price: ";
cin>>part_price;
cout<<"\n" << part_price <<endl;
cout<<"Please enter the part quantity: ";
cin>>part_quant;
cout<<"\n" << part_quant <<endl;
}
http://ideone.com/U31pb9
Just give yourself the output right away. To see what you were missing.
Fixed for whitespaces n stuff:
int main()
{
string part_num;
string part_des;
int part_price;
int part_quant;
cout<<"Please enter the part number: ";
getline( cin , part_num );
cout << "\n" << part_num <<endl;
cout<<"Please enter the part description: ";
getline( cin , part_des );
cout<< "\n" << part_des <<endl;
cout<<"Please enter the part price: ";
cin >> part_price;
cout << "\n" << part_price <<endl;
cout << "Please enter the part quantity: ";
cin >> part_quant;
cout << "\n" << part_quant <<endl;
}
Also think about using strings for the price and the quant as well and then convert them to integer if you want to keep using getline.

Answer 3

Try this, it should work:
#include <iostream>
using namespace std;
int main ()
{
int i;
cout << "Please enter an integer value: ";
cin >> i;
cout << "The value you entered is " << i;
cout << " and its double is " << i*2 << ".\n";
return 0;
}