Strings - Need assitance creating function headers & prototypes to pass a string to an other function.

[Zzuniga]

Why will my program not compile correctly when I both functions together?

Here is the gist of what I am suppose to be doing.

The goal of this program is to be able to enter in a phone-number as a string, and format it into the standard format, [phone].

With the first function we are suppose to enter in the phone-number, and then run it through a loop, and extract only the digits from that string and copy them to an other string.

Example: String_1 = (817)-733-5778

After Loop: New_String = 8177335778

Then in function two, we run the new string through a loop. If the phone number is exactly ten digits then it is put into standard format.

Example: New_String=8177335778

After Loop: String = [phone]

Here is what I have thus far

#include <iostream>
#include <string>
using namespace std;

//Function Prototypes 
void Phone_Number(string); 
string Modified_Number(string); 

int main()
{
	string Phone_Number_2; 

	Phone_Number(Phone_Number_2); 

	string New_Number = Modified_Number(Phone_Number_2); 

	cout << " The formatted number is " << New_Number << endl; 

	return 0;
}

void Phone_Number(string Phone_Number_2)

{
	string Phone_Number;
	getline(cin, Phone_Number);

	for (int Index = 0; Index < Phone_Number.length(); Index++)
	{
		int x = 0;
		string Phone_Number_2 = "" + Phone_Number[Index];
		if (Phone_Number[Index] <= '9' && Phone_Number[Index] >= '0')
		{
			Phone_Number_2[x] = Phone_Number[Index];
			cout << Phone_Number_2[x];
			x++;
		}
	}

}

string Modified_Number(string Phone_Number_2)

{
 int digit_length = 11;

	if (Phone_Number_2.length() >= digit_length)
		cout << "The phone number must be exactly 10 digits.\n";
	else
		cout << "The properly formatted number is "
		<< "(" << Phone_Number_2[0] << Phone_Number_2[1] << Phone_Number_2[2] << ")"
		<< " " << Phone_Number_2[3] << Phone_Number_2[4] << Phone_Number_2[5]
		<< "-" << Phone_Number_2[6] << Phone_Number_2[7] << Phone_Number_2[8] << Phone_Number_2[9]
		<< endl;

	return Modified_Number;
}

[Bdanielz]

Hi Zzuniga,

The reason your code will not compile is your string Modified_Number(string Phone_Number_2) function is not returning any string. Ether make it return a string, or set it as a void return type.

Let us know if you have any questions.

Best.

[Zzuniga]

Bdanielz,

Thank you for the reply! Can you send me links of articles on the topic of returning strings? Or better yet, could you show me how to return a string with a separate example code?

Thanks

[AbstractionAnon]

Line 56: Modified_Number is not a string. It's the address of your function.

PLEASE USE CODE TAGS (the <> formatting button) when posting code.
It makes it easier to read your code and also easier to respond to your post.
http://www.cplusplus.com/articles/jEywvCM9/
Hint: You can edit your post, highlight your code and press the <> formatting button.

[Bdanielz]

Hi Zzuniga,

Here are few examples using your problem as an example.

#include <iostream>

using namespace std;
//Function Prototypes
void Phone_Number(string);
string Modified_Number(string);
string Modified_Number_alt(string input);

int main() {
    string aPhoneNumber = "5552221111";


    // assigning a value by returning a string
    string aModifiedNumber = Modified_Number (aPhoneNumber);

    // printing the variable.
    cout << aModifiedNumber << endl;

    // just returning a value and printing, but not assigning a variable.


    cout << Modified_Number_alt ("5551111234") << endl;
    return 0;
}

// formatting the sting simluar to how you were printing it. 
string Modified_Number(string input) {
    const int phoneLen = 10;
    string formattedNumber = "(   )   -     ";  // making a blank template.

    // this will cover too short and too big.
    if (input.length () != phoneLen)
        cout << "The phone number must be exactly 10 digits.\n";
    else {
        int pos1 = 1;
        int pos2 = 0;
        // skip '(' and add 3 from input to formattedNumber
        int areaCodeLen = 3;
        for (int i = 0; i < areaCodeLen; ++i) {
            formattedNumber[pos1++] = input[pos2++];
        }
        // skip )
        pos1++;
        int prefixLen = 3;
        for (int i = 0; i < prefixLen; ++i) {
            formattedNumber[pos1++] = input[pos2++];
        }
        //skip -
        pos1++;
        int suffixLen = 4;
        for (int i = 0; i < suffixLen; ++i) {
            formattedNumber[pos1++] = input[pos2++];
        }

    }
    return formattedNumber;
}

// another way to format the string
string Modified_Number_alt(string input) {
    const int phoneLen = 10;

    // this will cover too short and too big.
    if (input.length () != phoneLen)
        cout << "The phone number must be exactly 10 digits.\n";
    else {
        input.insert (0, "(");
        input.insert (4, ")");
        input.insert (8, "-");

    }
    return input;
}

Read more about returning data using functions.
(int, string ect..)
http://www.cplusplus.com/doc/tutorial/functions/

Let us know if you have any questions!