棧和隊列
在出隊之前,一個輔助棧如果爲空的話需要把第一個棧中的所有元素彈出壓入這個棧中,棧頂的那個元素就是要出隊的元素;
如果輔助棧不爲空的話,棧頂元素就是要出隊的元素;
TwoStack.cpp:
#include <iostream>
#include <cstdio>
#include "Queue.h"
using namespace std;
void Test(char actual, char expected)
{
if(actual == expected)
printf("Test passed.\n");
else
printf("Test failed.\n");
}
int main()
{
CQueue<char> queue;
queue.appendTail('a');
queue.appendTail('b');
queue.appendTail('c');
char head = queue.deleteHead();
Test(head, 'a');
head = queue.deleteHead();
Test(head, 'b');
queue.appendTail('d');
head = queue.deleteHead();
Test(head, 'c');
queue.appendTail('e');
head = queue.deleteHead();
Test(head, 'd');
head = queue.deleteHead();
Test(head, 'e');
return 0;
}
Queue.h:
#ifndef _QUEUE_H_
#define _QUEUE_H_
#include <stack>
#include <exception>
using namespace std;
template <typename T> class CQueue
{
public:
CQueue(void);
~CQueue(void);
// 在隊列末尾添加一個結點
void appendTail(const T& node);
// 刪除隊列的頭結點
T deleteHead();
private:
stack<T> stack1;
stack<T> stack2;
};
template <typename T> CQueue<T>::CQueue(void)
{
}
template <typename T> CQueue<T>::~CQueue(void)
{
}
template<typename T> void CQueue<T>::appendTail(const T& element)
{
stack1.push(element);
}
template<typename T> T CQueue<T>::deleteHead()
{
if(stack2.size()<= 0)
{
while(stack1.size()>0)
{
T& data = stack1.top();
stack1.pop();
stack2.push(data);
}
}
if(stack2.size() == 0)
throw new exception();
T head = stack2.top();
stack2.pop();
return head;
}
#endif /*_QUEUE_H_*/
Queue.cpp:
#include "Queue.h"
#include <queue>
Makefile:
.PHONY:clean
CPP=g++
CFLAGS=-Wall -g
BIN=test
OBJS=TwoStack.o Queue.o
LIBS=
$(BIN):$(OBJS)
$(CPP) $(CFLAGS) $^ -o $@ $(LIBS)
%.o:%.cpp
$(CPP) $(CFLAGS) -c $< -o $@
clean:
rm -f *.o $(BIN)
測試結果:
Test passed.
Test passed.
Test passed.
Test passed.
Test passed.