Why doesn't the erase element function work?

I'm trying to write a program to manipulate a vector and save it in a text file. All the functions work except the erase element function, lines 371-377. Why isn't people.erase(position); working?

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#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<fstream>
#include<iomanip>
#include<stdlib.h>




using namespace std;




int fillVector();
int sortVector();
int printVector();
int saveVector();
int printBackup();
int loadVector();
int addSingleObject();
int addToVector();
int fillVector();
int eraseElement();



struct addressCard
{
string name;
string street;
string town;
string county;
string postCode;
string country;
int telephoneNumber;
};




// write to an output stream, object into a stream
ostream& operator<< ( ostream& stm, const addressCard& a )
    // write one string per line, end with a blank line
{
    return stm << a.name << '\n' << a.street << '\n' << a.town << '\n' 
<< a.county << '\n' << a.postCode << '\n' << a.country << "\n\n" ;
}

// read from an input stream
istream& operator>> ( istream& stm, addressCard& a )
{
    // read one line per string, ignore blank lines at the beginning

    // read the first line, after skipping over blank lines
    while( getline( stm, a.name ) && a.name.empty() ) ;

    // read the remaining lines
    if( getline( stm, a.street ) && getline( stm, a.town ) 
&& getline( stm, a.county ) && getline( stm, a.postCode ) 
&& getline( stm, a.country ) ) ; // do nothing more
    else a = {} ; // clear all fields in a

    return stm ;
}




bool genericSort(const addressCard &obj1, const addressCard &obj2) {
	if (obj1.name == obj2.name)
		if (obj1.street == obj2.street)
			if (obj1.town == obj2.town)
				if (obj1.county == obj2.county)
					if (obj1.postCode == obj2.postCode)
						return obj1.country < obj2.country;
					else
						return obj1.postCode < obj2.postCode; //same as the 
//correspondent if condition, replace == with <
				else
					return obj1.county < obj2.county;
			else
				return obj1.town < obj2.town;
		else
			return obj1.street < obj2.street;
	else
		return obj1.name < obj2.name;

}


enum BOOL { FALSE, TRUE };
int numberOfExtraPeople;
const unsigned numberOfPeople = 3;
string file_name = "data.txt";
vector<addressCard> people(numberOfPeople);
vector<addressCard> spareVector(numberOfExtraPeople); 




int main()
{
char choice;

BOOL exit = FALSE;
for (;;)
{
cout <<"(1) Fill vector (2) Sort vector (3) Print vector (4) Save file\n";
cout <<"(5) Print file (6) Load file (7) Add single object\n";
cout <<"(8) Add multiple objects (9) Erase element (0) Exit\n";
cin >> choice;


switch(choice)
{
case '0' :
exit=TRUE;
break;
case '1' : 
fillVector();
break;
case '2' :
sortVector();
break;
case '3' :
printVector();
break;
case '4' :
saveVector();
break;
case '5' :
printBackup();
break;
case '6' :
loadVector();
break;
case '7' :
addSingleObject();
break;
case '8' :
addToVector();
break;
case '9' :
eraseElement();
break;
default :
cout <<"Please select again.\n";
break;
} // end switch

if(exit)
break;
}

}




int fillVector()
{

cin.ignore();

for (vector<addressCard>::size_type i = 0; i!=numberOfPeople; ++i)
{
cout <<"Person# " <<i+1<< " name: " << endl;
getline(cin,people[i].name);

cout <<"Person# " <<i+1<< " street: " << endl;
getline(cin,people[i].street);

cout <<"Person# " <<i+1<< " town: " << endl;
getline(cin,people[i].town);

cout <<"Person# " <<i+1<< " county: " << endl;
getline(cin,people[i].county);

cout <<"Person# " <<i+1<< " postCode: " << endl;
getline(cin,people[i].postCode);

cout <<"Person# " <<i+1<< " country: " << endl;
getline(cin,people[i].country);

}

cout <<"\n\n";
}





int sortVector()
{

cout <<"Sorting....\n";

sort(people.begin(), people.end(), genericSort);
}





int printVector()
{
cout <<"Printing results....\n";

for (addressCard &n : people)
{
cout << n.name << endl;
cout << n.street << endl;
cout << n.town << endl;
cout << n.county << endl;
cout << n.postCode << endl;
cout << n.country << endl;

cout <<"\n\n";
}

cout <<"Printing raw vector....\n";

for (vector<addressCard>::size_type i = 0; i!=numberOfPeople; ++i)
{
cout <<people[i].name << endl;

cout <<people[i].street << endl;

cout << people[i].town << endl;

cout <<people[i].county << endl;

cout << people[i].postCode << endl;

cout <<people[i].country << endl;

cout <<"\n\n";

}

}





int saveVector()
{


cout <<"Writing to file....\n";

const string file_name = "data.txt" ;

        ofstream ofile(file_name) ;
        for( const addressCard& a : people ) ofile << a ; //vector 
//favourites of class type addressCard, object a iterates vector
// and writes it to text file
ofile.close();

}




int printBackup()
{

cout<<"Writing text file to screen...\n\n";

    string x;
    ifstream inFile;

    inFile.open("data.txt");
    if (!inFile) {
        cout << "Unable to open file";
        return(1); // terminate with error
    }

    while (getline(inFile,x)) {
cout << x << endl ;
}

    inFile.close();
}




int loadVector()
{
cin.ignore();

cout <<"Loading text file into existing vector....\n";

        ifstream ifile(file_name) ; //ifstream reads text file
        addressCard a ; //new object
        people.clear(); //clears existing vector
        cout << people.size() << " size of array after clear\n\n" ;        
        while( ifile >> a ) people.push_back(a) ; //object a reads from text
// file, fills existing vector people
        cout << people.size() << " items were read\n\n" ;

        for( const auto& a : people ) cout << a ;
}




int addSingleObject()
{

cout <<"Adding an element to the vector....\n";

addressCard addedObj;
addedObj = {"Jonathan Zebes","26 Grovsenor St","Chester","Cheshire",
"CH8 9PO","UK"};
people.push_back(addedObj);

}




int addToVector()
{

cout << "Adding several elements to the existing vector.\n";
cout << "How many elements would you like to add?\n";

cin>>numberOfExtraPeople;

cin.ignore();



for (vector<addressCard>::size_type i = 0; i!=numberOfExtraPeople; ++i)
{
cout <<"Person# " <<i+1<< " name: " << endl;
getline(cin,spareVector[i].name);

cout <<"Person# " <<i+1<< " street: " << endl;
getline(cin,spareVector[i].street);

cout <<"Person# " <<i+1<< " town: " << endl;
getline(cin,spareVector[i].town);

cout <<"Person# " <<i+1<< " county: " << endl;
getline(cin,spareVector[i].county);

cout <<"Person# " <<i+1<< " postCode: " << endl;
getline(cin,spareVector[i].postCode);

cout <<"Person# " <<i+1<< " country: " << endl;
getline(cin,spareVector[i].country);

}

cout <<"Copying spare vector to existing vector...\n";  
    for (int i=0; i<spareVector.size(); i++) 
        people.push_back(spareVector[i]); 
}




int eraseElement()
{
int position;
cout <<"What position would you like to erase?\n";
cin>>position;
cout <<"Erasing position" <<position<< "\n"; 	
people.erase(position);
}
Because erase expects an iterator, not an index.

 
people.erase(people.begin() + position);
The vector class erase function doesn't take an int as parameter.

http://www.cplusplus.com/reference/vector/vector/erase/

It takes an iterator.

Why isn't people.erase(position); working?

Because you are supplying the wrong data type for the method to work.

erase requires a vector iterator, or a range defined by iterators, to work.

https://en.cppreference.com/w/cpp/container/vector/erase
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