C++上机题目事务管理程序编译通过但是宕机请帮忙！！谢谢！

gf_zh 2009-02-06 10:49:51

代码如下，VC 6.0 下编译通过，运行时宕机，请帮忙指导！谢谢！
#include <iomanip.h>
class Date{
public:
int year;
int month;
int day;
Date();
Date(int x,int y,int z);
friend istream &operator>>(istream &is,Date &date);
int AddDays(int days);
int SubDays(int days);
};
/////////////////////////
class ICommand{
protected:
Date *num;
public:
ICommand();
virtual int execute()=0;
virtual void undo()=0;
};
//////////////////////////////////
class ForwardCommand:public ICommand{
private:
Date *pDate;
int days;
public:
ForwardCommand();
int execute();
void undo();

};
class BackwardCommand:public ICommand{
private:
Date *pDate;
int days;
public:
BackwardCommand();
int execute();
void undo();
};

///////////////////////////////
class TransactionManager{
private:
ICommand *tm[3];
int accnum;
public:
TransactionManager();
int addCommand ( ICommand* comm);
void begin();
void commit();
void rollBack();
};
///////////////////////////////////////////////////////////////////////////////////////////////////////999888
#include <iostream.h>
//#include "TransManager.h"

Date::Date(){
year=0;
month=0;
day=0;
}
Date::Date(int x,int y,int z){
year=x;
month=y;
day=z;
}
istream &operator>>(istream &is,Date &date){
cout<<"请输入年份:";
cin>>date.year;
cout<<"请输入月份:";
cin>>date.month;
cout<<"请输入哪天:";
cin>>date.day;
return is;
}
int Date::AddDays(int days){
int num;
num=day+days;
if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
{
if(num>31)
return 0;
}
else{
if(month==4||month==6||month==9||month==11)
if(num>30)
return 0;
else
if(month==2){
if(num>28)
return 0;
}
}

day=num;
return 1;
}
int Date::SubDays(int days){
int num;
num=day-days;
if(num<0)
return 0;
else
day=num;
return 1;
}
ICommand::ICommand(){
num=new Date;
}
ForwardCommand::ForwardCommand(){
cout<<"请输入初始的日期："<<endl;
cin>>*pDate;
cout<<"请输入要执行的数："<<endl;
cin>>days;
}
int ForwardCommand::execute(){
num->day=pDate->day+days;
cout<<"日期后延"<<num->day<<"天"<<endl;
return num->day;
}
void ForwardCommand::undo(){
delete num;
return;
}
BackwardCommand::BackwardCommand(){
cout<<"请输入初始的日期："<<endl;
cin>>*pDate;
cout<<"请输入要执行的数："<<endl;
cin>>days;
}
int BackwardCommand::execute(){
num->day=pDate->day-days;
cout<<"日期前推"<<num->day<<"天"<<endl;
return num->day;
}
void BackwardCommand::undo(){
delete num;
return;
}
/////////////////////////
TransactionManager::TransactionManager(){
for(int i=0;i<3;i++)
tm[i]=NULL;
accnum=0;
}
int TransactionManager::addCommand(ICommand *comm){

int succeed=1;
tm[accnum]=comm;
accnum++;
if(accnum==3)
return succeed=0;
else
return succeed;
}
void TransactionManager::begin(){
for(int i=0;i<3;i++)
tm[i]=NULL;
accnum=0;
cout<<"事务环境初始化完毕！"<<endl;
return;
}
void TransactionManager::commit(){
if(accnum==0){
cout<<"无事务，无法提交！"<<endl;
return;
}
for(int i=0;i<3;i++){
cout<<"第"<<i+1<<"个事务已提交"<<endl;
tm[i]->execute();
}
cout<<endl;
return;
}
void TransactionManager::rollBack(){
if(accnum==0){
cout<<"无事务，无法回滚！"<<endl;
return;
}
for(int i=0;i<3;i++){
tm[i]->undo();
delete tm[i];
accnum--;
cout<<"第"<<i+1<<"项事务已回滚！"<<endl;
}
cout<<endl;
return;
}
///////////////////////////////

int main()
{
TransactionManager tran;
ForwardCommand *forward;
BackwardCommand *backward;
char s;
int i;
int n=0;
while(n!=4){
cout<<"*******事务管理系统*********"<<endl;
cout<<"1:开始事务"<<endl;
cout<<"2:提交事务"<<endl;
cout<<"3:回滚事务"<<endl;
cout<<"4:退出系统"<<endl;
cout<<"请您选择：";
cin>>n;
cout<<endl;
switch(n){
case 1:
cout<<"现有两中事务："<<endl;
cout<<"1:日期后延命令；2：日期前推命令"<<endl;
cout<<"请问是否执行?(y/n)";
cin>>s;
while(s!='y'&&s!='n'){
cout<<"输入错误，请重新输入(y/n)";
cin>>s;
}
cout<<endl;
if(s=='n')
break;
else
{
for(i=0;i<2;i++){
if(i==0){
cout<<"输入错误，请重新输入(y/n)";
forward = new ForwardCommand;
cout<<"输入错误，请重新输入(y/n)";
if(tran.addCommand(forward))
cout<<"第"<<i+1<<"项事务添加成功！"<<endl;
else
cout<<"事务已满，无法添加!"<<endl;
}
if(i==1){
backward = new BackwardCommand;
if(tran.addCommand(backward))
cout<<"第"<<i+1<<"项事务添加成功！"<<endl;
else
cout<<"事务已满，无法添加!"<<endl;
}
}
}
cout<<endl;
break;
case 2:
tran.commit();
break;
case 3:
tran.rollBack();
break;
case 4:
break;
}
}
return 0;
}

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