NFA到DFA和DFA到MFA转换算法实现：C#语言代码示例

/**

NFA到DFA的转换 */ private void button7_Click(object sender, EventArgs e) { //获取NFA的开始状态 string[] startStates = startSymbol.Split(';').Select(x => x.Trim()).ToArray();

//获取NFA的终止状态 string[] endStates = endSymbol.Split(';').Select(x => x.Trim()).ToArray();

//获取NFA的符号集 string[] symbolSet = lines[2].Substring(lines[2].IndexOf(":") + 1).Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries);

//创建DFA的开始状态 string startState = string.Join(",", startStates);

//创建DFA的终止状态集 List dfaEndStates = new List();

//创建DFA的状态集 List dfaStates = new List();

//创建DFA的转移函数 Dictionary<string, Dictionary<string, string>> dfaTransitions = new Dictionary<string, Dictionary<string, string>>();

//将NFA的开始状态加入DFA的状态集 dfaStates.Add(startState);

//创建一个队列，用于存放DFA的状态 Queue queue = new Queue();

//将DFA的开始状态加入队列 queue.Enqueue(startState);

//循环处理队列中的状态 while (queue.Count > 0) { //取出队列中的状态 string currentState = queue.Dequeue();
```
 //将当前状态按照逗号分隔，得到NFA的状态集
 string[] nfaStates = currentState.Split(',');

 //创建一个字典，用于存放当前状态的转移函数
 Dictionary<string, string> currentTransitions = new Dictionary<string, string>();

 //循环处理NFA的符号集
 foreach (string symbol in symbolSet)
 {
     //创建一个列表，用于存放当前符号下的所有状态
     List<string> symbolStates = new List<string>();

     //循环处理NFA的状态集
     foreach (string nfaState in nfaStates)
     {
         //在NFA的转移函数中查找当前状态和当前符号下的所有状态
         foreach (ListViewItem item in listView1.Items)
         {
             if (item.SubItems[0].Text == nfaState && item.SubItems[1].Text == symbol)
             {
                 symbolStates.Add(item.SubItems[2].Text);
             }
         }
     }

     //去重
     symbolStates = symbolStates.Distinct().ToList();

     //将当前符号下的所有状态按照逗号连接，得到DFA的新状态
     string newState = string.Join(",", symbolStates);

     //如果新状态不在DFA的状态集中，将其加入状态集和队列中
     if (!dfaStates.Contains(newState) && !string.IsNullOrEmpty(newState))
     {
         dfaStates.Add(newState);
         queue.Enqueue(newState);
     }

     //将当前符号下的所有状态和新状态加入当前状态的转移函数中
     currentTransitions[symbol] = newState;
 }

 //将当前状态和转移函数加入DFA的转移函数中
 dfaTransitions[currentState] = currentTransitions;

 //如果当前状态包含NFA的终止状态，将其加入DFA的终止状态集中
 if (nfaStates.Intersect(endStates).Any())
 {
     dfaEndStates.Add(currentState);
 }
```
}

//创建DFA的结束状态 string endState = "终止状态集:" + string.Join(";", dfaEndStates);

//创建DFA的状态数 string stateCount = "状态数:" + dfaStates.Count;

//创建DFA的符号集 string symbols = "符号集:" + string.Join(";", symbolSet);

//创建DFA的文件内容 string dfaContent = startSymbol + "\n" + endState + "\n" + stateCount + "\n" + symbols + "\n";

//循环处理DFA的转移函数，将其加入文件内容中 foreach (string state in dfaTransitions.Keys) { foreach (string symbol in dfaTransitions[state].Keys) { string toState = dfaTransitions[state][symbol]; dfaContent += state + "\t" + symbol + "\t" + toState + "\n"; } }

//保存DFA文件 SaveFileDialog saveFileDialog = new SaveFileDialog(); saveFileDialog.Filter = "DFA文件(.dfa)|.dfa"; saveFileDialog.FileName = "DFA.txt"; if (saveFileDialog.ShowDialog() == DialogResult.OK) { string fileName = saveFileDialog.FileName; File.WriteAllText(fileName, dfaContent, Encoding.UTF8); }

MessageBox.Show("转换完成！"); }

/**

DFA到MFA的转换 */ private void button9_Click(object sender, EventArgs e) { //获取DFA的开始状态 string[] startStates = startSymbol.Split(';').Select(x => x.Trim()).ToArray();

//获取DFA的终止状态集 string[] endStates = endSymbol.Split(';').Select(x => x.Trim()).ToArray();

//获取DFA的符号集 string[] symbolSet = lines[3].Substring(lines[3].IndexOf(":") + 1).Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries);

//创建MFA的开始状态 string startState = string.Join(",", startStates);

//创建MFA的终止状态集 List mfaEndStates = new List();

//创建MFA的状态集 List mfaStates = new List();

//创建MFA的转移函数 Dictionary<string, Dictionary<string, string>> mfaTransitions = new Dictionary<string, Dictionary<string, string>>();

//将DFA的开始状态加入MFA的状态集 mfaStates.Add(startState);

//创建一个队列，用于存放MFA的状态 Queue queue = new Queue();

//将MFA的开始状态加入队列 queue.Enqueue(startState);

//循环处理队列中的状态 while (queue.Count > 0) { //取出队列中的状态 string currentState = queue.Dequeue();
```
 //将当前状态按照逗号分隔，得到DFA的状态集
 string[] dfaStates = currentState.Split(',');

 //创建一个字典，用于存放当前状态的转移函数
 Dictionary<string, string> currentTransitions = new Dictionary<string, string>();

 //循环处理DFA的符号集
 foreach (string symbol in symbolSet)
 {
     //创建一个列表，用于存放当前符号下的所有状态
     List<string> symbolStates = new List<string>();

     //循环处理DFA的状态集
     foreach (string dfaState in dfaStates)
     {
         //在DFA的转移函数中查找当前状态和当前符号下的所有状态
         foreach (ListViewItem item in listView2.Items)
         {
             if (item.SubItems[0].Text == dfaState && item.SubItems[1].Text == symbol)
             {
                 symbolStates.Add(item.SubItems[2].Text);
             }
         }
     }

     //去重
     symbolStates = symbolStates.Distinct().ToList();

     //将当前符号下的所有状态按照逗号连接，得到MFA的新状态
     string newState = string.Join(",", symbolStates);

     //如果新状态不在MFA的状态集中，将其加入状态集和队列中
     if (!mfaStates.Contains(newState) && !string.IsNullOrEmpty(newState))
     {
         mfaStates.Add(newState);
         queue.Enqueue(newState);
     }

     //将当前符号下的所有状态和新状态加入当前状态的转移函数中
     currentTransitions[symbol] = newState;
 }

 //将当前状态和转移函数加入MFA的转移函数中
 mfaTransitions[currentState] = currentTransitions;

 //如果当前状态包含DFA的终止状态，将其加入MFA的终止状态集中
 if (dfaStates.Intersect(endStates).Any())
 {
     mfaEndStates.Add(currentState);
 }
```
}

//创建MFA的结束状态 string endState = "终止状态集:" + string.Join(";", mfaEndStates);

//创建MFA的状态数 string stateCount = "状态数:" + mfaStates.Count;

//创建MFA的符号集 string symbols = "符号集:" + string.Join(";", symbolSet);

//创建MFA的文件内容 string mfaContent = startSymbol + "\n" + endState + "\n" + stateCount + "\n" + symbols + "\n";

//循环处理MFA的转移函数，将其加入文件内容中 foreach (string state in mfaTransitions.Keys) { foreach (string symbol in mfaTransitions[state].Keys) { string toState = mfaTransitions[state][symbol]; mfaContent += state + "\t" + symbol + "\t" + toState + "\n"; } }

//保存MFA文件 SaveFileDialog saveFileDialog = new SaveFileDialog(); saveFileDialog.Filter = "MFA文件(.mfa)|.mfa"; saveFileDialog.FileName = "MFA.txt"; if (saveFileDialog.ShowDialog() == DialogResult.OK) { string fileName = saveFileDialog.FileName; File.WriteAllText(fileName, mfaContent, Encoding.UTF8); }

MessageBox.Show("转换完成！");