public class DFALexer { public static boolean dfaRecognize(Map<String, Object> dfa, String inputStr) {要求:给定当前状态和当前输入,根据transition找到下一状态,并更新为当前状态,,完善该函数代码
时间: 2023-06-25 20:04:52 浏览: 96
public static boolean dfaRecognize(Map<String, Object> dfa, String inputStr) {
String currentState = (String) dfa.get("start_state");
Map<String, Map<String, String>> transition = (Map<String, Map<String, String>>) dfa.get("transition");
Set<String> finalStates = new HashSet<>((List<String>) dfa.get("final_states"));
for (int i = 0; i < inputStr.length(); i++) {
String input = String.valueOf(inputStr.charAt(i));
Map<String, String> trans = transition.get(currentState);
if (trans.containsKey(input)) {
currentState = trans.get(input);
} else {
return false;
}
}
return finalStates.contains(currentState);
}
注:该代码实现了给定一个DFA(确定性有限状态自动机)以及输入字符串,判断该字符串是否被该DFA所接受的功能。其中,dfa是该DFA的一个表示,包括起始状态(start_state),终止状态(final_states),以及转移函数(transition)。
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