C++常用操作

C++常用操作

数组

输入二维数组

#include <iostream>
#include <vector>


using namespace std;
int main() {
        int r = 0, c = 0;
    cout << "输出行数 r:";//规定二维数组行数
    cin >> r;
    cout << "输入列数 c:";//规定二维数组列数
    cin >> c;
    vector<vector<int>> array(r, vector<int>(c));//定义二维数组

    for (int i = 0; i < r; i++)//输入r*c的二维数组
    {
        for (int j = 0; j < c; j++) {
                cin >> array[i][j];
        }
    }
	return 0;
}

链表

创建、初始化并打印链表

#include <iostream>

using namespace std;

struct Node{
    int val;
    Node* prev;// 上一个节点
    Node* next;// 下一个节点
};


class List{
public:
    Node * head;
    List(){
        head = nullptr;
    }

    void Create(){
        Node* p = new Node();
        p->val = 0;
        p->next = NULL;
        head = p;

        int n;
        cout << "请输入链表的长度：";
        cin >> n;

        cout << "请输入第 1 个值：";
        cin >> p->val;

        for(int i = 1;i < n;i++){
            Node *q = new Node();
            q->next = NULL;
            cout << "请输入第 " << i+1 <<" 个值：";
            cin >> q->val;
            p->next = q;  //  连接两个节点
            p = q;  //  指针指向添加的节点，方便之后添加
        }
    }


    void Output()//输出链表的数据域和指针域
    {
        if (head == NULL) {
            cout << "该表为空表" << endl;
        }

        Node *current = head;
        while (current != NULL) {
            cout << current->val << endl;
            current = current->next;

        }
    }

    ~List(){

    }
};
int main() {
    List A;
    A.Create();
    A.Output();

    return 0;
}

在pos位置后面插入节点

//在pos位置后面插入一个节点
    void ListInsertPos(int pos, int val)
    {
        Node* newNode = new Node();
        newNode->val = val;
        newNode->next = NULL;

        Node* cur = head;
        int i = 0;
        while(cur != nullptr && i < pos - 1)
        {
            i++;
            cur = cur->next;
        }
        Node* tmp = cur->next;
        cur->next = newNode;
        newNode->next = tmp;
    }

删除pos位置节点

void ListDeletePos(int pos)
    {
        if(head != nullptr && pos == 0)
        {
            Node* tmp = head;
            head = head->next;
            delete tmp;
        }
        else{
            int i = 0;
            Node* cur = head;
            while(cur != nullptr && i < pos - 1)
            {
                i++;
                cur = cur->next;
            }
            Node* tmp = cur->next;
            cur->next = cur->next->next;
            delete tmp;
        }
    }