CareerCup

I think they're looking for a class or strategy, that starts small, and adds space (copying the old data across) as needed, /but as a proportion of what is already there/, as is done with C++'s STL 'vector'. A factor of 2 is frequently used, ie every time you need more memory, double what's there, but you could use any proportion, 1.2, 1.5, whatever, trading off more wasted space against speed at any time. Using a proportion gives you /amortized constant time/ for the reallocation. If you were to purely /add/, say, 10 elements each time, you'd get O(n^2) time.

Use list implementation, ArrayList. It is a dynamic DS. If required can be converted into an array using list.toArray method.

int size;
int *array;
cout<<"no of elements:";
cin>>size;
array=new int;
for(i=0;i<size;i++) {cin>>array[i];}

{int a;
int *array;
scanf("%d",&a);
array=(int *)malloc(a*sizof(int));}