Can someone break down this code line by line for me and tell me what each line means?

#include using namespace std;

int getLinesFromFile(string fileName, int arr[], int length)

{

ifstream f;

f.open(fileName.c_str());

if(!f.good())

{

return -1;

}

int curr_index = 0;

while(!f.eof() && curr_index < length)

{

if (f >> arr[curr_index])

curr_index++;

}

f.close();

return curr_index;

}