correct sequence of various phases of systems approach
Systems development life cycle The SDLC is not a methodology per se, but rather a description of the phases in the life cycle of a software application. These phases (broadly speaking) are, investigation, analysis, design, build, test, implement, and maintenance and support. All software development methodologies (such as the more commonly known waterfall and scrum methodologies) follow the SDLC phases but the method of doing that varies vastly between methodologies. In the Scrum methodology, for example, one could say a single user story goes through all the phases of the SDLC within a single two-week sprint. Contrast this to the waterfall methodology, as another example, where every business requirement (recorded in the analysis phase of the SDLC in a document called the Business Requirements Specification) is translated into feature/functional descriptions (recorded in the design phase in a document called the Functional Specification) which are then all built in one go as a collection of solution features typically over a period of three to nine months, or more. These methodologies are obviously quite different approaches yet, they both contain the SDLC phases in which a requirement is born, then travels through the life cycle phases ending in the final phase of maintenance and support, after-which (typically) the whole life cycle starts again for a subsequent version of the software application.
Algorithm As an effective method, an algorithm can be expressed within a finite amount of space and time[1] and in a well-defined formal language[2] for calculating a function.[3] Starting from an initial state and initial input (perhaps empty),[4] the instructions describe a computation that, when executed, proceeds through a finite[5] number of well-defined successive states, eventually producing "output"[6] and terminating at a final ending state. The transition from one state to the next is not necessarily deterministic; some algorithms, known as randomized algorithms, incorporate random input.[7]