Dynamic array initialization to 0?
int main()
{
int arraySize;
int arrayMain[arraySize-1];
cout << "\n\nEnter Total Number of Elements in Array.\n\n";
cin >> arraySize;
arrayMain[arraySize-1]={0};
cout <<"\n\n" <<arrayMain;
return 0;
}
my compiler hangs while compiling the above code. I am confused about how to set a dynamic array to 0?
You are using std::vector
:
std::vector<int> vec(arraySize-1);
Your code is invalid because 1) is arraySize
not initialized and 2) you cannot have variable length arrays in C ++. So either use a vector or allocate memory dynamically (this is what it std::vector
does internally):
int* arrayMain = new int[arraySize-1] ();
Notice at ()
the end - he used a value to initialize the elements, so the array will have its elements set to 0.
If you must use a dynamic array, you can use value initialization (although std::vector<int>
would be the recommended solution):
int* arrayMain = new int[arraySize - 1]();
Check the result of the input operation to make sure the variable has been assigned the correct value:
if (cin >> arraySize && arraySize > 1) // > 1 to allocate an array with at least
{ // one element (unsure why the '-1').
int* arrayMain = new int[arraySize - 1]();
// Delete 'arrayMain' when no longer required.
delete[] arrayMain;
}
Note the usage cout
:
cout <<"\n\n" <<arrayMain;
will print the address of the array arrayMain
, not every single element. To print each user, you need to index each element in turn:
for (int i = 0; i < arraySize - 1; i++) std::cout << arrayMain[i] << '\n';