// 将逆波兰表达式转换为一棵树
// parameters:
// return:
// NULL
// 其他
BerNode ChangeRPNToTree()
{
BerNode param = null;
int nRet;
Token token = null;
for (int i = 0; i < this.m_PolandArray.Count; i++)
{
token = m_PolandArray[i];
Debug.Assert(token != null, "");
if (token.m_nType == TYPE_OPERAND)
{
nRet = HandleOperand(token.m_strToken);
if (nRet == -1)
{
throw new Exception("HandleOperand Fail!");
// return null;
}
}
else
{
nRet = HandleOperator(token.m_nType,
token.m_strToken);
if (nRet == -1)
{
return(null);
}
}
}
PopFromArray(out param);
/*
* DeleteFile("polandtree.txt");
* pParam->DumpToFile("polandtree.txt");
*/
// 如果pParam->m_ChildArray.GetSize() > 1
// 表示不能为21，必须在21下面有一个1
m_Subroot.AddSubtree(param);
return(param);
}
// 处理operator
// parameters:
// return:
// NULL
// 其他
int HandleOperator(int nType,
string strToken)
{
BerNode param = null;
BerNode subparam = null;
int nRet;
int i;
param = new BerNode();
param.m_cClass = ASN1_CONTEXT;
param.m_cForm = ASN1_CONSTRUCTED;
param.m_uTag = 1;
param.m_strDebugInfo = "operator [" + strToken + "]";
// 从堆栈中弹出两个操作数对象
for (i = 0; i < 2; i++)
{
nRet = PopFromArray(out subparam);
if (nRet == -1)
{
return(-1);
}
param.AddSubtree(subparam);
}
// 创建op
BldOperator(param,
nType,
strToken);
// 结果又入栈
PushToArray(param);
return(0);
}