c_string or const char?

[Andre20]

Hello, it will not allow me to enter Line numbers, or even preview it at all.


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


using namespace std;

void getFileName (string& fileName)
{
cout << "Enter File Name: ";
getline (cin, fileName);
}

int binarySearch(string list[], int first, int last, string aString)
{
int loc=0, mid=last/2;

if(first>last)
loc=-1;
else
{
mid = (first+last)/2;
if(aString == list[mid])
loc = mid;
else if(aString < list [mid])
loc = binarySearch(list, first, mid-1, aString);
else
loc = binarySearch(list,mid+1, last, aString);
}
return loc;
}

const int MAX = 500;

int main()
{

string str, artistList[MAX];
string fileName = "\0";
ifstream inFile;
int num = 0;

int results;
int first;
int last;
string list;
string aString;



getFileName(fileName);
inFile.open(fileName.c_str() );



if(!inFile)
{
cout << "Can't open file " << fileName << endl;
return -1;
}

getline(inFile, str);
while(!inFile.eof())
{
cout << str << endl;
getline(inFile, str);
}

cout << "Enter Artist Name: ";
getline(cin, str);

results = binarySearch(list, first, last, aString);

if (results == -1)
cout << "Artist Not In List! \n";

else
{
cout << "That artist is located at element " << results << "in the array \n";
}


inFile.close();

system("pause");
return 0;
}

[Repeater]

Which line is line 72?

Use code tags. http://www.cplusplus.com/articles/jEywvCM9/

[Andre20]

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


using namespace std;

void getFileName (string& fileName)
{
	cout << "Enter File Name: ";
	getline (cin, fileName);
}

int binarySearch(string list[], int first, int last, string aString)
{
	int loc=0, mid=last/2;

	if(first>last)
		loc=-1;
	else
	{
		mid = (first+last)/2;
		if(aString == list[mid])
			loc = mid;
		else if(aString < list [mid])
			loc = binarySearch(list, first, mid-1, aString);
		else 
			loc = binarySearch(list,mid+1, last, aString);
	}
	return loc;
}

const int MAX = 500;

int main()
{
	
	string str, artistList[MAX];
	string fileName = "\0";
	ifstream inFile;
	int num = 0;
	
	int results;
	int first;
	int last;
	string list;
	string aString;
	

	
	getFileName(fileName);
	inFile.open(fileName.c_str() );
	

	
	if(!inFile)
	{
		cout << "Can't open file " << fileName << endl;
		return -1;
	}
	
	getline(inFile, str);
	while(!inFile.eof())
	{
		cout << str << endl;
		getline(inFile, str);
	}
	
	cout << "Enter Artist Name: ";
	getline(cin, str);
	
	results = binarySearch(list, first, last, aString);
	
	if (results == -1)
		cout << "Artist Not In List! \n";
		
	else
	{
		cout << "That artist is located at element " << results << "in the array \n";
	}
		
		
	inFile.close();
	
	system("pause");
	return 0;
}

[Repeater]

int binarySearch(string list[], int first, int last, string aString)

Four parameters.

1) array of string
2) int
3) int
4) string


You trying to call it:
results = binarySearch(list, first, last, aString);

1) list - string
2) first - int
3) last - int
4) aString - string

See the problem?

[coder777]

Line 72: list will be an empty single string while binarySearch(...) requires an array of strings.

You can simplify the loop on line 63:

	while(getline(inFile, str)) // Note: getline() return false in case of an error such as eof
	{
		cout << str << endl;
	}

Since list needs to be an array you may do the following:

	string list[100];
	for(last = 0; (last < 100) && getline(inFile, str); ++last)
	{
		list[last] = str;
		cout << str << endl;
	}
...
	results = binarySearch(list, 0, last, aString);

[Andre20]

I do see the problem. I am calling an array of string and not a string. I have made some changes, however i've tried a few things and can't seem to correct it. This is what my code looks like now....

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


using namespace std;

void getFileName (string& fileName)
{
	cout << "Enter File Name: ";
	getline (cin, fileName);
}

int binarySearch(string artistList[], int first, int last, string aString)
{
	int loc=0, mid=last/2;

	if(first>last)
		loc=-1;
	else
	{
		mid = (first+last)/2;
		if(aString == artistList[mid])
			loc = mid;
		else if(aString < artistList [mid])
			loc = binarySearch(artistList, first, mid-1, aString);
		else 
			loc = binarySearch(artistList,mid+1, last, aString);
	}
	return loc;
}

const int MAX = 500;

int main()
{
	
	string str, artistList[MAX];
	string fileName = "\0";
	ifstream inFile;
	int num = 0;
	
	int results;
	int first;
	int last;
	string aString;
	

	
	getFileName(fileName);
	inFile.open(fileName.c_str() );
	

	
	if(!inFile)
	{
		cout << "Can't open file " << fileName << endl;
		return -1;
	}
	
	getline(inFile, str);
	while(!inFile.eof())
	{
		cout << str << endl;
		getline(inFile, str);
	}
	
	cout << "Enter Artist Name: ";
	getline(cin, str);
	
	results = binarySearch(string artistList[MAX], first, last, aString);
	
	if (results == -1)
		cout << "Artist Not In List! \n";
		
	else
	{
		cout << "That artist is located at element " << results << "in the array \n";
	}
		
		
	inFile.close();
	
	system("pause");
	return 0;
}

[MikeyBoy]

At line 71:

results = binarySearch(string artistList[MAX], first, last, aString);

That's not the syntax you use for calling a function. You don't specify the argument types, in a function call.

[dhayden]

IN addition to what MikeyBoy said, you need to fill the artistList array with values before you can search it. Should it comtain the lines from the input file?

[Andre20]

Yes, it should be from the input file