自己创建一个异常

#ifndef STACK_H
#define STACK_H

#include <deque>
#include <exception>

template<class T>
class Stack
{
protected:
std::deque<T> c;
public:
class ReadEmptyStack : public std::exception   //exception 是标准异常，
{
public:
virtual const char * what() const throw()
{
return "read empty stack 堆栈是空的";
}
};
bool empty() const
{
return c.empty();
}
void push(const T& elem)
{
c.push_back(elem);
}
T pop()  // 抛出数据，
{
if(c.empty())
{
throw ReadEmptyStack();
}
T elem(c.back());
c.pop_back();
return elem;
}
T& top()  // 读数据，
{
if(c.empty())
{
throw ReadEmptyStack();
}
return c.back();
}
};

#endif

<pre name="code" class="cpp">#include <iostream>#include "Stack.h"using namespace std;int main(){try{Stack<int> s;s.push(4);s.push(7);cout << "pop : " << s.pop() << endl;cout << "top: " << s.top() << endl;cout << "pop: " << s.pop() << endl;cout << "top: " << s.top() << endl;}catch(const exception& e){cerr << "发生异常：" << e.what() << endl;}cout << "xiao cui " << endl;return 0;}