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LNK2019 Error

EdWar82 (43)
I am getting this error in my compiler and unable able to figure out what the issue is so far..

Error 1 error LNK2019: unresolved external symbol "int __cdecl showBooksByAuthor(int,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)" (?showBooksByAuthor@@YAHHV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z) referenced in function _main

Error 2 error LNK1120: 1 unresolved externals 1 1

Here is just the beginning of what I have. What is that error pointing to?!?

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  #include <iostream>
#include <iomanip>
#include <fstream>
#include <string>

using namespace std;

// Declare Variables

const int ARRAY_SIZE = 1000;

int showBooksByAuthor(int count, string name);
int showBooksByTitle(int count, string title);

string pathName;
string bookTitle[ARRAY_SIZE];
string bookAuthor[ARRAY_SIZE];



// Functions

int main()
{
	// char backupFile;
	char reply;

	int count = 0;


	string name;
	string title;

	do
	{
		// Output
		cout << "Welcome to Edward's Libarary Database. " << endl;
		cout << "Please enter the name of the backup file: ";
		// cin >> backupFile;

		cout << "Enter Q to (Q)uit, Search (A)uthor, Search (T)itle, (S)how all: ";
		cin >> reply;

		// Selection
		switch (reply)
		{
		case'a':
		case'A':

			char nameAuthor;

			cout << "Author's Name: ";
			cin >> nameAuthor;
			if (count <= 0)
			{
				cout << "No Author found!" << endl;
			}
			else
			{
				cout << showBooksByAuthor(count, name) << "found! " << endl;
			}
			break;
		case't':
		case'T':

			char nameTitle;

			cout << "Title: ";
			cin >> nameTitle;

			break;
		case's':
		case'S':
			break;
		case'q':
		case'Q':
			break;
		default:
			cout << "Invalid Input." << endl;
			break;
		}

		
	} while (reply != 'Q' && reply != 'q');

	system("pause");
	return 0;
}

int loadData(string pathname)
{
	int count = 0;
	ifstream inFile;

	inFile.open(pathName);

	if (!inFile)
	{
		cout << "Cannot open backup file" << endl;
		return -1;
	}
	else
	{
		cout << "File opened" << endl;
	}
	while (!inFile.eof())
	{
		getline(inFile, bookTitle[count]);
		getline(inFile, bookAuthor[count]);
		count++;
	}
	return count;
}

void showAll(int count)
{

	int i;
	for (i = 0; i < count; i++)
	{
		// cout << bookTitle[i] << " " << "(" << bookAuthor[i] << ")" << endl;
	}

}
ChajusSaib (96)
Have you defined
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2
 
int showBooksByAuthor(int count, string name);
int showBooksByTitle(int count, string title);
. If so make sure to pass the files they are defined in to the compiler. Also a tip would be to declare functions in a header.
e.g g++ main.cpp showBooks.cpp ....

The code you have provided does not defined them it just declares them.
Last edited on
MiiNiPaa (8886)
You are trying to call nonexisting function showBooksByAuthor at line 60
EdWar82 (43)
Ah! I see it now. Thank you!
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