The Stepwise refinement techniques in data structures :-
Step-wise refinement is a technique for software development using a top-down, structured approach to solving a problem. It allows the developer to use a controlled method of developing an algorithm that will eventually solve a given problem.
Basically, step-wise refinement involves the use of a generalized approach to a problem, perhaps written in pseudo-code. The next step would be to fill in one of the holes in the code. The pseudo-code describes a general, non-specific way to solve the problem deferring the actual decisions until last minute. That way the developer can assign place-holders in the logic until they are actually needed.
Then, each step involves the use of refining (adding the logic) a step in the development of the algorithm to make it more specific, doing so one step at at time.
When everything has been refined you have a complete program; however, it takes multiple steps (step-wise refining) to get to that point where a complete, syntactically correct program emerges.