88 lines
2.2 KiB
C++
88 lines
2.2 KiB
C++
// 设计一个模板类 Stack，实现基本的堆栈功能，包括入栈（push）、出栈（pop）、获取栈顶元素（top）和判断栈是否为空（isEmpty）等操作。
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// 【提示】Stack栈结构的特性是FILO(先进后出)
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#include <iostream>
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using namespace std;
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template <typename T>
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class Stack
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{
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private:
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int capacity; // 容量
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int size; // 已存数量计数器
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T *arr; // 指向数组的指针
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public:
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Stack(int capacity)
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{
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this->capacity = capacity;
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this->arr = new T[capacity];
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this->size = 0;
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}
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Stack(const Stack<T> &other)
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{
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this->capacity = other.capacity;
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this->size = other.size;
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this->arr = new T[capacity];
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for (int i = 0; i < size; i++)
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{
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this->arr[i] = other.arr[i];
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}
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}
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~Stack()
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{
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delete[] arr;
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}
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public:
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// & 用于返回引用，支持链式调用
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Stack &push(T val)
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{
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if (size == capacity)
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{
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cout << "栈已经满了!" << endl;
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return *this;
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}
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arr[size++] = val;
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return *this; // 返回自身，支持链式调用
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}
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T pop()
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{
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if (size == 0)
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{
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cout << "栈已经空了!" << endl;
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return -1;
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}
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return arr[--size]; // 先减再取，因为size是计数器，指向下一个空位
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}
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T top()
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{
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if (size == 0)
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{
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cout << "栈已经空了!" << endl;
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return -1;
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}
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return arr[size - 1]; // 直接取顶部元素
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}
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string isEmpty()
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{
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return size == 0 ? "栈空" : "栈未空"; // 判断计数器是否为 0，为 0 表示栈空
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}
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};
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int main()
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{
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Stack<int> s(5);
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s.push(1).push(2).push(3).push(4).push(5);
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cout << s.pop() << endl; // 5
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cout << s.pop() << endl; // 4
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cout << s.top() << endl; // 3
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cout << s.isEmpty() << endl; // 栈未空
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cout << s.pop() << endl; // 3
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cout << s.pop() << endl; // 2
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cout << s.pop() << endl; // 1
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cout << s.isEmpty() << endl; // 栈空
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cout << s.pop() << endl; // 栈已经空了! -1
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return 0;
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}
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