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SyedMuddasir
what is mean by data structure?
I'm not sure how detailed you'd like an answer, so let's start very slowly. A data structure is a form of organizing data in the computer memory. How could we organize a list? We can connect all the elements of the list so that one element knows where is the other. So we can save the place in memory of the first element of the list. To find the element, we ask the first element how we can get to the next. It will tell us and we move to the next. How do we get to the next one? We ask the current element where we can find the next. Does that answer your question?
Like friend say above. Also we can use the simple idea the book tells us, just constructor and selector. You will see this on the rest of the book.
A data structure is a particular way of organizing data. In computer science, a data structure must additionally provide a way to store the data in a computer, in such a way that it can be used efficiently.