Delete Zero in ArrayList in C++ - c++

Question

Inside the ArrayList I'm trying to delete all possible 0's that are appended as input, but for now it only deletes just one 0, no matter where it is located. But seems like I can't delete more than one zero at the time. How can I fix this?
void AList::elimZeros(){
int i;
int curr = 0;
for(i=0; i < listSize; i++) {
if ( (listArray[i] != 0 ) && (curr<listSize) ){
listArray[curr] = listArray[i];
curr++;
}
else if (listArray[i] == 0 )
{
listArray[curr] = listArray[i+1];
listSize--;
curr++;
}
}
}
This is the class for the ADT
class AList : public List {
private:
ListItemType* listArray; // Array holding list elements
static const int DEFAULT_SIZE = 10; // Default size
int maxSize; // Maximum size of list
int listSize; // Current # of list items
int curr; // Position of current element
// Duplicates the size of the array pointed to by listArray
// and update the value of maxSize.
void resize();
public:
// Constructors
// Create a new list object with maximum size "size"
AList(int size = DEFAULT_SIZE) : listSize(0), curr(0) {
maxSize = size;
listArray = new ListItemType[size]; // Create listArray
}
~AList(); // destructor to remove array
This is the input I'm testing with:
int main() {
AList L(10);
AList L2(20);
L.append(10);
expect(L.to_string()=="<|10>");
L.append(20);
expect(L.to_string()=="<|10,20>");
L.append(30);
L.append(0);
L.append(40);
L.append(0);
L.append(0);
expect(L.to_string()=="<|10,20,30,0,40>");
L.elimZeros();
expect(L.to_string()=="<|10,20,30,40>");
assertionReport();
}

Answer 1

It'd be helpful if you posted the class code for AList. Think you confused Java's ArrayList type, but assuming you're using vectors you can always just do:
for (int i = 0; i < listSize; i++) {
if(listArray[i] == 0) listArray.erase(i);
}
EDIT: Assuming this is the template of for the AList class, then there is simply a remove() function. In terms of your code, there are two issues.
You reference listSize in the for loop, then decrement it inside of the loop. Each iteration evaluates the value separately so you're reducing the number of total loop iterations and stopping early.
The other thing is if the entry is zero you shouldn't increment curr and set listArray[curr] = listArray[i+1]. This is basically assuming the next entry will not be a zero. So if it is, then you're copying the element and moving to the next. Your if statement can be cleaned up with:
if (listArray[i] == 0) {
listSize--;
} else {
listArray[curr] = listArray[i];
curr++;
}