c语言循环队列（C++循环队列）

本文实例为大家分享了C++实现循环队列的具体代码，供大家参考，具体内容如下

circularQueue.h

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 #pragma once #pragma once #ifndef CIRCULARQUEUE_H #define CIRCULARQUEUE_H #include<iostream> #include<ostream> using std::cout; using std::cin; using std::endl; using std::ostream; template<class T> class cirQueue; template<typename T> class cirQueue { public: cirQueue(int sz); ~cirQueue(); void push(const T& elem);//进队 void pop(T& elem);//出队 bool empty();//查看队列是否为空 int getSize();//返回队列中元素的个数 void clearQueue();//清空队列中的元素 void print();//打印队列中的元素 int getfront() { return front; } int getrear() { return rear; } bool getTop(T& elem);//读取队列首个元素 template<typename T> friend ostream& operator<<(ostream& os, cirQueue<T>& queue); private: bool _full()const;//判断队列是否已满 int maxsize;//队列最大的空间 T* element;//存放于队列中的元素数组 int front;//模拟队头指针 int rear;//模拟队尾指针 }; template<typename T> cirQueue<T>::cirQueue(int sz) { maxsize = sz; element = new T[maxsize]; if (element == nullptr) cout << "内存分配失败" << endl; front = 0; rear = 0; } template<typename T> cirQueue<T>::~cirQueue() { if (element != nullptr) delete element; } //进队 template<typename T> void cirQueue<T>::push(const T& elem) {//需要保证队尾指针位置与首个元素相差一个位置 if (rear > (maxsize - 1)) rear -= maxsize ; if (front > (maxsize - 1)) front -= maxsize ; if (!_full()) {//队列未满的情况 element[rear++] = elem;//队尾向后移动一位 //++rear; } else { cout << "队列已满，不能插入！" << endl; return; } } //出队 template<typename T> void cirQueue<T>::pop(T& elem) { if (rear > (maxsize - 1)) rear -= (maxsize - 1); if (front > (maxsize - 1)) front -= (maxsize - 1); if (!empty()) {//队列未空的情况 elem = element[front++];//队头向后移动一位 element[front - 1] = 0;//置零 } else { cout << "队列已空！" << endl; return; } } //查看队列是否为空 template<typename T> bool cirQueue<T>::empty() { if (front == rear)//待定 return true; return false; } //返回队列中元素的个数 template<typename T> int cirQueue<T>::getSize() { int num = 0; if (front <= rear) return rear - front; else return maxsize - front + rear + 1; } //清空队列中的元素 template<typename T> void cirQueue<T>::clearQueue() { if (!empty()) { int Index = 0; while (front < rear) {//front逼近rear element[front++] = 0; if (front == rear) return; } if (rear < front) { while (front <= maxsize - 1)//删除front至数组尾端的数据 element[front++] = 0; front -= maxsize; while (front < rear) {//删除front至rear的数据 element[front++] = 0; if (front == rear) return; } } } } //打印队列中的元素 template<typename T> void cirQueue<T>::print() {//与clearQueue函数原理一致，将front替换为Index if (!empty()) { int Index = front; while (Index < rear) { cout << element[Index++] << " "; if (Index == rear) { cout << endl; return; } } if (rear < Index) { while (Index <= maxsize - 1) cout << element[Index++] << " "; Index -= maxsize; while (Index < rear) { cout << element[Index++] << " "; if (Index == rear) { cout << endl; return; } } } } } //读取队列首个元素 template<typename T> bool cirQueue<T>::getTop(T& elem) { if (!empty()) { elem = element[front]; return true; } return false; } template<typename T> ostream& operator<<(ostream& os, cirQueue<T>& queue) { os << "队列中的元素数量为：" << queue.getSize() << endl; return os; } //判断队列是否已满 template<typename T> bool cirQueue<T>::_full()const { if (front - rear == 1 || front - rear == -maxsize + 1) return true; return false; } #endif // !CIRCULARQUEUE_H

main.cpp

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 #include"CircularQueue.h" int main() { cirQueue<int> cq(20); int a = 0; for (int i = 0; i < 19; i++) { cq.push(i); } cq.print(); cout << cq; for (int i = 0; i < 20; i++) { cq.pop(a); } cout << cq;//此时front=rear=19 cout << cq.getfront() << " " << cq.getrear() << endl; //for (int i = 19; i < 25; i++) //{ // cq.push(i); //} cq.push(19); cq.print(); cout << cq.getfront() << " " << cq.getrear() << endl; cout << endl << endl; cq.push(20); cq.getTop(a); cout << a << endl; cq.print(); cout << cq.getfront() << " " << cq.getrear() << endl; return 1; }