I. Introduction
THE question of how macromolecules fold to attain specific shapes is fundamental to biology since the function of molecules is largely determined by structure [1]. Ribonucleic acid (RNA) is a molecule made up of a chain of nucleotides consisting of adenine (A), cytosine (C). guanine (G), and uracil (U), An RNA strand folds onto itself by forming hydrogen bonds between GC, AU, and GU, and their respective mirror images. It is widely believed that RNA molecules are closely related to the molecules from which life originally evolved.