// 创建LR(1)文法的分析表
private void calcAnalyzeList()
{
// 求 移进 列
var anaList = new List <KeyValuePair <string, List <string> > >();
List <string> rowData = new List <string>()
{
};
rowData.Add("符号");
for (int i = 0; i < graphMatrixCount; i++)
{
rowData.Add(i.ToString());
}
anaList.Add(new KeyValuePair <string, List <string> >("状态", rowData));
List <char> text = new List <char>();
foreach (char c in page.terminator.Text)
{
text.Add(c);
}
text.Sort();
text.Add('#');
int indexCount = 0;
foreach (char c in text) // 枚举每个非终结符（对应ACTION列）
{
rowData = new List <string>()
{
};
rowData.Add(c.ToString());
for (int i = 0; i < graphMatrixCount; i++)
{
rowData.Add("");
}
for (int i = 0; i < graphMatrixCount; i++)
{
for (int j = 0; j < graphMatrixCount; j++)
{
if (graphMatrix[i, j] == c)
{
rowData[i + 1] = "S" + j;
}
}
}
anaList.Add(new KeyValuePair <string, List <string> >("ACTION " + indexCount++, rowData));
}
// 求 规约 列
foreach (string line in page.lstProduce.Items) // HASH产生式方便由产生式确定产生式所在下标
{
int pos = line.IndexOf('：');
getIndexByProduct[line.Substring(pos + 1).Replace("ε", "")] = Int32.Parse(line.Substring(0, pos));
}
flag = true;
for (int i = 0; i < allStates.Count; i++)
{
foreach (var item in allStates[i].items)
{
if (item.Key.EndsWith("●"))
{
int index = getIndexByProduct[item.Key.Substring(0, item.Key.Length - 1)];
foreach (char c in item.Value)
{
string append = (index > 0) ? ("r" + index) : "acc";
int j;
for (j = 0; j < anaList.Count; j++)
{
if (anaList[j].Value[0].Equals(c.ToString()))
{
break;
}
}
if (anaList[j].Value[i + 1].Length > 0)
{
anaList[j].Value[i + 1] += "/" + append;
if (c != '#' || i + 1 != 1) // 不是接受项则产生冲突
{
flag = false;
}
}
else
{
anaList[j].Value[i + 1] = append;
}
}
}
}
}
// 求 GOTO 列
text.Clear();
for (int i = 1; i < page.nterminator.Text.Length; i++)
{
text.Add(page.nterminator.Text[i - 1]);
}
foreach (char c in text) // 与移进处理类似
{
rowData = new List <string>()
{
};
rowData.Add(c.ToString());
for (int i = 0; i < graphMatrixCount; i++)
{
rowData.Add("");
}
for (int i = 0; i < graphMatrixCount; i++)
{
for (int j = 0; j < graphMatrixCount; j++)
{
if (graphMatrix[i, j] == c)
{
rowData[i + 1] = j.ToString();
}
}
}
anaList.Add(new KeyValuePair <string, List <string> >("GOTO " + indexCount++, rowData));
}
// 作为HashMap、转置拷贝到全局（用于分析例句）
foreach (var pair in anaList)
{
if (!pair.Key.Equals("状态"))
{
for (int i = 1; i < pair.Value.Count; i++)
{
if (!analyzeList.ContainsKey(i - 1))
{
analyzeList[i - 1] = new Dictionary <char, string>();
}
analyzeList[i - 1][pair.Value[0][0]] = pair.Value[i];
}
}
}
page.tbLRList.ItemsSource = DataSourceCreator.ToDataSource(anaList);
if (!flag)
{
MessagePage.Show("由于冲突的产生，所以该文法不符合LR(1)文法！");
}
}
// 构造LR(1)文法的DFA
private void calcDefiniteFA()
{
int count = 0;
List <string> extList = new List <string>();
extList.Add(count++.ToString() + "：" + "Φ → " + page.cbBegin.SelectedItem);
foreach (string line in page.lstProduce.Items)
{
extList.Add(count++.ToString() + "：" + line[0] + " → " + line.Substring(4));
}
page.lstProduce.Items.Clear();
foreach (string line in extList)
{
page.lstProduce.Items.Add(line);
}
page.nterminator.Text += 'Φ';
var init_state = new EnclosedState();
init_state.items.Add("Φ → ●" + page.cbBegin.SelectedItem, new List <char>()
{
'#'
});
init_state = calcEnclosed(init_state);
allStates.Add(init_state);
List <List <KeyValuePair <int, char> > > release = new List <List <KeyValuePair <int, char> > >();
// release[i][j]记录第i个状态可以通过字符release[i][j].Value推出第release[i][j].Key个状态
for (int i = 0; i < allStates.Count; i++)
{
var front = allStates[i].items;
var graphAdj = new List <KeyValuePair <int, char> >();
var enableChr = new List <char>(); // 对推新状态的途径字符判重
foreach (var pair in front) // 找出所有不重复可推状态
{
int pos = pair.Key.IndexOf('●') + 1;
if (pos < pair.Key.Length && !enableChr.Contains(pair.Key[pos]))
{
char c = pair.Key[pos];
enableChr.Add(c); // 对推新状态的途径字符判重
// 对经过c字符转向新状态
EnclosedState esbuild = new EnclosedState();
foreach (var trans in front) // 查询当前状态所有产生式中，●后是c的条目
{
int np = trans.Key.IndexOf('●') + 1;
if (np < trans.Key.Length && trans.Key[np] == c) // 找到一条符合项
{
string next = trans.Key.Remove(np - 1, 1).Insert(np, "●");
esbuild.items.Add(next, trans.Value);
}
}
esbuild = calcEnclosed(esbuild);
int j;
for (j = 0; j < allStates.Count; j++) // 新状态已存在
{
if (EnclosedState.Equals(esbuild.items, allStates[j].items)) // 判断是否完全匹配
{
graphAdj.Add(new KeyValuePair <int, char>(j, c));
break;
}
}
if (j >= allStates.Count) // 不存在新状态则创建
{
graphAdj.Add(new KeyValuePair <int, char>(j, c));
allStates.Add(esbuild);
}
}
}
release.Add(graphAdj);
}
graphMatrixCount = allStates.Count;
graphMatrix = new char[graphMatrixCount, graphMatrixCount];
for (int i = 0; i < graphMatrixCount; i++)
{
foreach (var j in release[i])
{
graphMatrix[i, j.Key] = j.Value;
}
}
int tot = allStates[0].items.Count;
for (int i = 1; i < allStates.Count; i++)
{
tot = Math.Max(tot, allStates[i].items.Count);
}
// 显示DFA状态转换矩阵
var dfaMatrix = new List <KeyValuePair <string, List <string> > >();
List <string> stateList = new List <string>();
for (int i = 0; i < graphMatrixCount; i++)
{
stateList.Add("状态" + i);
}
dfaMatrix.Add(new KeyValuePair <string, List <string> >("DFA", stateList));
for (int i = 0; i < graphMatrixCount; i++)
{
stateList = new List <string>();
for (int j = 0; j < graphMatrixCount; j++)
{
if (graphMatrix[j, i] > 0)
{
StringBuilder sb = new StringBuilder();
sb.Append("从状态" + j + "：\n");
foreach (var item in allStates[j].items)
{
sb.Append(item.Key);
sb.Append(" ， ");
sb.Append(item.Value[0]);
for (int k = 1; k < item.Value.Count; k++)
{
sb.Append('/');
sb.Append(item.Value[k]);
}
sb.Append('\n');
}
for (int l = allStates[j].items.Count; l < tot; l++)
{
sb.Append('\n');
}
sb.Append("经过字符 " + graphMatrix[j, i] + " 转变为状态" + i + "：\n");
foreach (var item in allStates[i].items)
{
sb.Append(item.Key);
sb.Append(" ， ");
sb.Append(item.Value[0]);
for (int k = 1; k < item.Value.Count; k++)
{
sb.Append('/');
sb.Append(item.Value[k]);
}
sb.Append('\n');
}
for (int l = allStates[i].items.Count; l < tot; l++)
{
sb.Append('\n');
}
stateList.Add(sb.ToString());
}
else
{
StringBuilder sb = new StringBuilder();
for (int l = 0; l <= tot; l++)
{
sb.Append("\n\n");
}
stateList.Add(sb.ToString());
}
}
dfaMatrix.Add(new KeyValuePair <string, List <string> >("状态" + i, stateList));
}
page.tbDfa.ItemsSource = DataSourceCreator.ToDataSource(dfaMatrix);
}
// 对语句进行分析与验证
private void calcAnalyzeCode()
{
if (!flag)
{
page.legal.Text = "无解";
return;
}
string text = page.sentence.Text;
int nStep = 1;
List <string> step = new List <string>()
{
"(" + nStep++.ToString() + ")"
}, stateStack = new List <string>()
{
"0"
},
operStack = new List <string>()
{
"#"
}, inputString = new List <string>()
{
text + '#'
},
actionOper = new List <string>(), gotoOper = new List <string>();
// 从第一步开始求解分析过程
while (flag)
{
// 当前状态s，当前字符c
int s = Int32.Parse(stateStack[stateStack.Count - 1].Substring(stateStack[stateStack.Count - 1].LastIndexOf(',') + 1));
char c = inputString[inputString.Count - 1][0];
string got = analyzeList[s][c];
if (got.Length == 0)
{
flag = false;
actionOper.Add("出错");
gotoOper.Add("");
break;
}
if (got.Contains("acc")) // 遇到'#'且可以为acc则一定为接受
{
actionOper.Add("接受");
gotoOper.Add("");
break;
}
char type = got[0];
int next = Int32.Parse(got.Substring(1));
step.Add("(" + nStep++.ToString() + ")");
if (type == 'S') // 移进
{
actionOper.Add("移进 " + next);
gotoOper.Add("");
stateStack.Add(stateStack[stateStack.Count - 1] + "," + next);
operStack.Add(operStack[operStack.Count - 1] + c);
inputString.Add(inputString[inputString.Count - 1].Substring(1));
}
else // 规约
{
actionOper.Add("规约 " + next);
string line = (string)page.lstProduce.Items[next];
line = line.Substring(line.IndexOf('：') + 1).Replace("ε", "");
char left = line[0];
string right = line.Substring(4);
string stackCut = stateStack[stateStack.Count - 1];
for (int i = 0; i < right.Length; i++)
{
stackCut = stackCut.Remove(stackCut.LastIndexOf(','));
}
int new_top = Int32.Parse(stackCut.Substring(stackCut.LastIndexOf(',') + 1)); // 弹斩后栈顶
int target = Int32.Parse(analyzeList[new_top][left]); // 获取GOTO目标
stateStack.Add(stackCut + "," + target);
if (right.Length > 0)
{
operStack.Add(operStack[operStack.Count - 1].Remove(operStack[operStack.Count - 1].Length - right.Length) + left);
}
else
{
operStack.Add(operStack[operStack.Count - 1] + left);
}
inputString.Add(inputString[inputString.Count - 1]);
gotoOper.Add("转至 " + target);
}
}
page.legal.Text = (flag) ? "正确" : "错误";
var showAnalyze = new List <KeyValuePair <string, List <string> > >();
showAnalyze.Add(new KeyValuePair <string, List <string> >("步骤", step));
showAnalyze.Add(new KeyValuePair <string, List <string> >("状态栈", stateStack));
showAnalyze.Add(new KeyValuePair <string, List <string> >("符号栈", operStack));
showAnalyze.Add(new KeyValuePair <string, List <string> >("输入串", inputString));
showAnalyze.Add(new KeyValuePair <string, List <string> >("ACTION", actionOper));
showAnalyze.Add(new KeyValuePair <string, List <string> >("GOTO", gotoOper));
page.tbAnalyze.ItemsSource = DataSourceCreator.ToDataSource(showAnalyze);
}
// 计算FIRST,FOLLOW集
private void calcFirstAndFollow()
{
// 求 FIRST 集
flag = true;
while (flag)
{
flag = false;
visited.Clear();
foreach (char c in page.nterminator.Text)
{
first_dfs(c);
}
}
// 求 FOLLOW 集
follow[(char)page.cbBegin.SelectedItem] = new List <char>()
{
'#'
};
flag = true;
while (flag)
{
flag = false;
visited.Clear();
foreach (char c in page.nterminator.Text)
{
follow_dfs(c);
}
}
// 构造二维表并显示
var dicFfset = new List <KeyValuePair <string, List <string> > >();
List <string> ntList = new List <string>(), firstList = new List <string>(),
followList = new List <string>();
foreach (char c in page.nterminator.Text)
{
// 列表
ntList.Add(c.ToString());
StringBuilder sb = new StringBuilder();
// 构造FIRST集
sb.Remove(0, sb.Length);
first[c].Sort();
foreach (char t in first[c])
{
sb.Append(t);
sb.Append(' ');
}
firstList.Add(sb.ToString());
// 构造FOLLOW集
sb.Remove(0, sb.Length);
follow[c].Sort();
foreach (char t in follow[c])
{
sb.Append(t);
sb.Append(' ');
}
followList.Add(sb.ToString());
}
dicFfset.Add(new KeyValuePair <string, List <string> >("非终结符", ntList));
dicFfset.Add(new KeyValuePair <string, List <string> >("FIRST 集", firstList));
dicFfset.Add(new KeyValuePair <string, List <string> >("FOLLOW 集", followList));
page.tbFfset.ItemsSource = DataSourceCreator.ToDataSource(dicFfset);
}
