24点游戏,用c++实现
源代码在线查看： calculate.cpp
// Caculate.cpp: implementation of the CCalculate class.
//
//////////////////////////////////////////////////////////////////////
#include "stdafx.h"
#include
#include "Calculate.h"
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif
#define MAXPRIORITY 4 //优先级
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
IMPLEMENT_SERIAL(CCalculate, CObject, 0)//序列化
CCalculate::CCalculate()
{
m_nPos=0;
m_pRoot=NULL;
m_strExpression="0";
m_strWrongMessage="";
m_bIsValid=FALSE;
}
CCalculate::CCalculate(const CString& strExpression)
{
// m_strStep=strExpression;
m_strExpression=strExpression+'\0'+'\0';
m_strExpression.Replace(" ","");
m_nPos=0;
m_pRoot=NULL;
m_strWrongMessage="";
m_bIsValid=FALSE;
}
CCalculate::~CCalculate()
{
FreeTree(m_pRoot);
}
void CCalculate::FreeTree(CNode* nod)
{//释放树节点
if (nod==NULL) return;
if (nod->left!=NULL) FreeTree(nod->left);
if (nod->right!=NULL) FreeTree(nod->right);
delete nod;
}
//生成一个树
int CCalculate::MakeTree()
{
//表达式为空
if (m_strExpression.IsEmpty())
return 0;
FreeTree(m_pRoot); // Eliberarea memoriei ocupate de arbore
m_pRoot = NULL;
m_nPos = 0;//m_nPos为结点在树中的编号
m_pRoot = AddSub();
if (m_strExpression[m_nPos]!='\0'||!m_strWrongMessage.IsEmpty())
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少操作符!";
FreeTree(m_pRoot);
m_pRoot = NULL;
}
if (m_pRoot == NULL)
return m_nPos;
else return -1;
}
//构造一个结点
CNode* CCalculate::AddSub()
{//加减
CNode* nod;
CNode* left = MultiplyDivide();
CNode* right;
if (left == NULL)
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少操作数";
return NULL;
}
while ((m_strExpression[m_nPos]=='-') || (m_strExpression[m_nPos]=='+'))
{
nod=new CNode;
nod->left=left;
nod->operate=m_strExpression[m_nPos];
nod->prior=4;
m_nPos++;
right = MultiplyDivide();
nod->right=right;
if (right == NULL)
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少'+'或'-'的操作数!";
FreeTree(nod);
return NULL;
}
left = nod;
}
return left;
}
//调用了Putere()函数
CNode* CCalculate::MultiplyDivide()
{//乘除
CNode* nod;
CNode* left = Putere();
CNode* right;
if (left == NULL) return NULL;
while ((m_strExpression[m_nPos]=='*') || (m_strExpression[m_nPos]=='/'))
{
nod=new CNode;
nod->left=left;
nod->operate=m_strExpression[m_nPos];
nod->prior=3;
m_nPos++;
right = Putere();
nod->right=right;
if (right == NULL)
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少'×'或'÷'的操作数!";
FreeTree(nod);
return NULL;
}
left = nod;
}
return left;
}
//求幂的函数 返回的都是一个结点
CNode* CCalculate::Putere()
{//幂
CNode* nod = NULL;
CNode* arb1 = Factor();
CNode* arb2;
if (arb1 == NULL) return NULL; // In caz de eroare terminate
while (m_strExpression[m_nPos]=='^')
{
nod=new CNode;
nod->left=arb1;
nod->operate=m_strExpression[m_nPos];
nod->prior=1;
m_nPos++;
arb2 = Factor();
nod->right=arb2;
if (arb2 == NULL)
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少'^'的操作数!";
FreeTree(nod);
return NULL; // In caz de eroare terminate
}
arb1 = nod;
}
return arb1;
}
//m_strExpression为表达式的值
CNode* CCalculate::Factor()
{//括号和绝对值、相反数
CNode* nod = NULL,*nod2 = NULL,*left = NULL; //表达式中有可能为''
while(m_strExpression[m_nPos] == ' ' && m_strExpression[m_nPos] != '\0')
m_nPos++;
if (m_strExpression[m_nPos]=='-')//substration
{
nod = new CNode;
m_nPos++;
// nod->right = AddSub();//something wrong;
// nod->right = MultiplyDivide();///
nod->right=Putere();
if (nod->right == NULL)
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少'-'(负数)的操作数!";
FreeTree(nod);
return NULL;
}
else if(nod->right->operate!='@')
{
left = new CNode;
left->left=NULL;
left->operate='@';
left->data=-1;
nod->left=left;
nod->operate='*';
nod->prior=0;//将优先级设为0，是因为需要括号的运算。如:---3应变为(-1*(-1*(-3)))
}
else
{
nod->left=NULL;
nod->data=-1*nod->right->data;
delete nod->right;
nod->right=NULL;
nod->operate='#';
nod->prior=0;
}
return nod;
}
if (m_strExpression[m_nPos]=='(')//left bracket
{
m_nPos++;
nod = AddSub();
if (nod == NULL) return NULL;
if (m_strExpression[m_nPos]!=')')
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少右括号')'!";
FreeTree(nod);
return NULL;
}
nod->prior=0;
m_nPos++;
return nod;
}
else if (m_strExpression[m_nPos]=='|')//abs
{
m_nPos++;
nod2 = AddSub();
if (nod2 == NULL) return NULL;
if (m_strExpression[m_nPos]!='|')
{
if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="缺少绝对值操作符'|'!";
FreeTree(nod);
return NULL;
}
nod = new CNode;
nod->left=nod2;
nod->right=NULL;
nod->operate='|';
nod->prior=0;
m_nPos++;
return nod;
}
else return Operand();
return nod;
}
//operator
CNode* CCalculate::Operand()
{//操作数
int nStartPos;//开始位置
CNode* nod = NULL;
CNode* result = NULL;
nStartPos = m_nPos;
if (m_strExpression[m_nPos]=='\0') result = NULL;
if (isdigit(m_strExpression[m_nPos])) // 数字
{
while (isdigit(m_strExpression[m_nPos]) || (m_strExpression[m_nPos]=='.'))
m_nPos++;
nod = new CNode;
nod->left = NULL;
nod->right = NULL;
nod->operate = '@';
nod->data = atof(m_strExpression.Mid(nStartPos,m_nPos-nStartPos));//convert the CString to data
result = nod;
}
return result;
}
double CCalculate::Calculate(CNode* node)
{
if (node==NULL)
{
// AfxMessageBox(m_strWrongMessage);
return -1;
}
double oper1=0.0,oper2=0.0;
if(node->left==NULL&&node->right==NULL)
return node->data;
else
{
oper1=Calculate(node->left);//取左边的数
oper2=Calculate(node->right);//取右边的数
//calculation
double result=GetValue(node->operate,oper1,oper2);
// MakeStep(oper1,oper2,node->operate,result);
return result;
}
}
//calculation
double CCalculate::GetValue(char operate,double oper1,double oper2)
{
switch(operate)
{
case '*': return oper1*oper2;
case '/'://特殊的情况
{
if (oper2==0)
{
// cout if(m_strWrongMessage.IsEmpty())
m_strWrongMessage="除数不能为零!";
// AfxMessageBox("除数不能为零!",MB_ICONSTOP|MB_OK);
return 0;
}
return oper1/oper2;
}
case '+': return oper1+oper2;
case '-': return oper1-oper2;
case '|': return fabs(oper1);
case '^': return pow(oper1,oper2);
}
return 0;
}
void CCalculate::Serialize(CArchive& ar)
{
CObject::Serialize(ar);
if (ar.IsStoring())
{
/* ar ar ar.Write(&m_logpen, sizeof(LOGPEN));
ar ar.Write(&m_logbrush, sizeof(LOGBRUSH));*/
}
else
{
// get the document back pointer from the archive
/* m_pDocument = (CMathDoc*)ar.m_pDocument;
ASSERT_VALID(m_pDocument);
ASSERT_KINDOF(CMathDoc, m_pDocument);
WORD wTemp;
ar >> m_m_nPosition;
ar >> wTemp; m_bPen = (BOOL)wTemp;
ar.Read(&m_logpen,sizeof(LOGPEN));
ar >> wTemp; m_bBrush = (BOOL)wTemp;
ar.Read(&m_logbrush, sizeof(LOGBRUSH));*/
}
}
BOOL CCalculate::IsValid(CString* pMessage, int* pPos)
{
if(MakeTree()!=-1)
{
if(pPos!=NULL)
*pPos=m_nPos;
if(pMessage!=NULL)
*pMessage=m_strWrongMessage;
m_bIsValid=FALSE;
return FALSE;
}
if(pPos!=NULL)
*pPos=-1;
if(pMessage!=NULL)
*pMessage="";
m_bIsValid=TRUE;
return TRUE;
}
double CCalculate::GetResult()
{
if(!m_bIsValid) return 0;
return Calculate(m_pRoot);
}
void CCalculate::ResetExp(const CString &strExp)
{
m_strExpression=strExp+'\0'+'\0';
}
