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L04 FSA: NFSA Traversal Traversing NFSA o NFSA has choice points. What to do? Which path to pursue? o Parallel traversal: Make all possible choices (and store in possible current states). * After consuming an input symbol, take all possible arcs from all possible current states. * When string ends, if one of the current states is an accepting state, accept the string. o Backtracking traversal: Follow one choice at a time, but return and follow another choice if necessary. - If there is a choice point, follow the next choice. (Keep track of choice points and the choices made therein, using a stack.) - When string ends, and cur-state is an accepting state, return ACCEPT. - Else go back to previous choice point undo the consumption of string. - Make next choice (record new choice in stack) o Look-ahead: Look ahead in the input to decide which path to take..........................................NEXT PREVIOUS INDEX