c++ Not able to add an element in the array [closed] - c++

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I am fairly new to c++. I am trying to add another element in the array. The function should change the array and the number of items in the array after the addEntry function is completed, but it doesn't. If I use the display function to show the array, only the original array is shown. Please help.
#include<iostream>
#include<string>
using namespace std;
const int MAXSIZE = 10; // total size of array
void display(string[], int);
void addEntry(string[], int&);
int main()
{
string name[MAXSIZE] = {"raj","casey","tom","phil"};
int numEntries = 4; // number of elements in the array
string choice; // the user choice to add an element or display or exit
cout<<numEntries<<" names were read in."<<endl;
do
{
cout<<endl<<"Enter menu choice (display, add, quit): ";
getline(cin,choice);
if (choice == "display")
{
display(name, numEntries);
cout<<endl;
}
else if (choice == "add")
{
addEntry(name, numEntries);
cout<<endl;
}
else
{
cout<<"bye"<<endl;
}
} while (choice!="quit");
system ("pause");
return 0;
}
void display(string name[], int numEntries)
{
for (int i = 0; i < numEntries; i++)
{
cout<<name[i]<<endl;
}
return;
}
void addEntry(string name[], int& numEntries)
{
if (numEntries<MAXSIZE-1)
{
numEntries++;
cout<<"Enter name of the person to add: ";
getline(cin,name[numEntries]);
cout << "Entry added.";
return;
}
else
{
cout<<"There is not enough space is in the array to add a new entry!";
return;
}
}

Answer 1

getline(cin,name[numEntries]);
numEntries is the number of valid entries in your array. name[numEntries] is the element that is following the last valid entry. Use name[numEntries-1].
Or even better, use std::vector instead of C arrays, after all, you are writing in C++.

Answer 2

Your program works, you are just pointing the the wrong location in your array in addEntry. Remember that arrays in C++ are 0-based, try incrementing the value of numEntries AFTER inserting the element in your array, for example:
void addEntry(string name[], int& numEntries)
{
if (numEntries<MAXSIZE)
{
cout<<"Enter name of the person to add: ";
getline(cin,name[numEntries++]);
cout << "Entry added.";
return;
}
else
{
cout<<"There is not enough space is in the array to add a new entry!";
return;
}
}

Answer 3

The bug in your code is in the following lines:
numEntries++;
cout<<"Enter name of the person to add: ";
getline(cin,name[numEntries]);
You need to increment numEntries after the call to getline. Use:
cout<<"Enter name of the person to add: ";
if ( getline(cin,name[numEntries]) )
{
// Increment only if getline was successful.
numEntries++;
}