No, it doesn’t. The capacity of a vector never decreases. That isn’t mandated by the standard but it’s so both in standard library implementations of VC++ and g++. In order to set the capacity just enough to fit the size, use the famous swap trick vector<T>().swap(foo); In C++11 standard, you can do it more explicitly: … Read more
I’m curious, what do you need it for? You should know that the capacity is not (as it may sound) an upper limit of how much you can put into the ArrayList. It’s a value representing how much data you can put into the list, without forcing it to reallocate it internal array. Basically, the … Read more
The default capacity of StringBuilder is 16 characters (I used .NET Reflector to find out).
Actually, it starts with a Capacity of 0. When you add the first element, the current implementation allocates a capacity of 4. After that, the capacity keeps doubling if expansion is needed, to guarantee amortized O(1) operation. Keep in mind that this is the current behavior. You shouldn’t rely on it to be the case. … Read more
You may be able to get an approximate idea by using the JSON methods to turn the whole localStorage object to a JSON string: JSON.stringify(localStorage).length I don’t know how byte-accurate it would be, especially with the few bytes of added markup if you’re using additional objects – but I figure it’s better than thinking you’re … Read more
If you know in advance what the size of the ArrayList is going to be, it is more efficient to specify the initial capacity. If you don’t do this, the internal array will have to be repeatedly reallocated as the list grows. The larger the final list, the more time you save by avoiding the … Read more