modifiable arrays - c++

Question

So, I know some Python but I thought that I should try to add some c++ to that knowledge. This is the code I've written that I'm playing with (it's actually a rewrite of some python code). It adds some song data to a class (or a multidimensional array inside a class). So far so good. Most of it work. But I'm stuck at the delSong method. I don't think I could implement this with arrays, so It's seems like I'm at a dead end. I read a little about vectors, but they won't let med delete an item in the middle. How could I get further? Shall I abandon arrays for something else? But what would that be?
#include <iostream>
#include <string>
using namespace std;
class Jukebox{
public:
void addSong(string artist, string title, string filename) {
songs [songsCounter][0] = artist;
songs [songsCounter][1] = title;
songs [songsCounter][2] = filename;
songsCounter++;
}
void printSong (int song) {
cout << songs[song][0] << " - ";
cout << songs[song][1] << " : ";
cout << songs[song][2] << endl;
}
void printSongs () {
int song;
for (song=0; song<songsCounter; song++ ) {
cout << songs[song][0] << " - ";
cout << songs[song][1] << " : ";
cout << songs[song][2] << endl;
}
}
void delSong(int song) {
// Some code here
}
private:
int songsCounter;
string songs [512][3];
};
int main() {
Jukebox jbox;
jbox.addSong("U2", "Magnificent", "U2-Magnificent.mp3");
jbox.addSong("Sting", "Englishman in New York", "Sting-Englishman_in_New_York.mp3");
jbox.addSong("U2", "One", "U2-One.mp3");
jbox.printSongs();
return 0;
}
In my python code I actually using an in memory sqlite3 db. But I could as well write it with a simple list of tuples. And that is a similar approach to what I'm trying to do here. But an in memory sqlite database would also be a possible way for me to do this in c++. But it does'nt look very easy either to implement?
One more thing, I also want to add a sort method later so please have that in mind when you suggest a solution so I don't get to another dead end... :)

Answer 1

Vectors do allow deletion in the middle (look for the erase function), albeit not at the greatest speed.
I'd recomend using a vector of structures instead of a multidimensional array.
struct song {
string artist;
string title;
string filename;
};
And then in your Jukebox:
vector<song> songs;
The vector grows as needed and keeps track of its own size, contrary to the array.
For sorting, there's std::sort function in the <algorithm> header.

Answer 2

First, add a constructor
Jukebox()
{
//do initialization here
}
You can delete a middle item in a vector.
http://www.cplusplus.com/reference/stl/vector/erase/
vector<unsigned int> myvector;
// set some values (from 1 to 10)
for (i=1; i<=10; i++)
myvector.push_back(i);
// erase the 6th element
myvector.erase (myvector.begin()+5);
Another approach, with the least code modification would be to move all the songs FOLLOWING the song to be deleted to the left by 1 and then decrement songCounter.
//Assuming song 1 is the song at index 0 and songCounter points to the first
//empty element in the array
//ex: 1,2,3,4,5 becomes 1,3,4,5
void delSong(int song) {
if(song <= 0) return;
if(song < songCounter-1) //we don't want to delete song 500 if we only have 20
{
song--;
while (song != songCounter)
{
songs[song][0] = songs[song+1][0];
songs[song][1] = songs[song+1][1];
songs[song][2] = songs[song+1][2];
song++;
}
}
//this handles case of deleting the last song in addition to the above case
if(song < songCounter)
{
songCounter--;
}
}