Abstract: In many aspects, the systems and methods of the invention are directed to sequencing of carbohydrates by mass spectrometry using computational approaches. The systems and methods utilize data derived from sequential mass spectrometry, in which a carbohydrate is fragmented to form products, each of which may then be fragmented further, gradually disassembling the carbohydrate. The systems and methods according to the principles of the invention resolve the tree-like structure of the original carbohydrate by examining the different ways in which disassembly occurs and then applying a set of inference rules that are at least based on mathematical constraints imposed on such tree-like structures.