2610 List Add

你的任务是完成一条能实现加法功能的单向链表，需要实现的函数在头文件已给出。

假如现在有 123 与 234 两个数字，那么他们在链表中的存储结构将会是 ： 3->2->1与 4->3->2

注意到这里的链表只允许从前端插入，你也可以把这个特殊的链表当做栈来处理。

输入的数字不会有负数且不会有前导0的输入。也就是说，输入的数字中不会出现0,更不会有0001这样的输入

Sample input

123123

Sample output

Input two NumbersAfter 123 + 123246After 246 + 123369

Provided Codes

main.cpp

#include "ListAdd.hpp"using std::cout;using std::endl;using std::cin;int main() {    string s1, s2;    // 0 < s1.length(),s2.length() <= 10000    cout << "Input two Numbers" << endl;    cin >> s1 >> s2;    List l1(s1), l2(s2);    List l3 = l1 + l2;    cout << "After " << l1 << " + " << l2 <<endl;    cout << l3 << endl << "Size : " << l3.size() << endl;    List l4;    l4 = l3 + l1;    cout << "After " << l3 << " + " << l1 << endl;    cout << l4 << endl << "Size : " << l4.size() << endl;}

ListAdd.hpp

#ifndef _LIST_ADD_#define _LIST_ADD_#include <iostream>using std::string;using std::ostream;class List {  private:      struct node {          int val;          node* next;          node(int v, node* n = 0):val(v), next(n){}      };      node* head;      int _size;  public:      List();      List(const List& other);      List(const string & num);      void clear();      void push_front(int val);   // 在头部插入数值      List operator+(const List& other);    //在这里进行链表加法实现      List& operator=(const List& other);   // 赋值操作重载      int size() const;      ~List();      friend ostream& operator<<(ostream & os, const List &  out);      // 输出数字，无需换行};#endif

Submission

ListAdd.cpp

 #include "ListAdd.hpp"#include <iostream>#include <sstream>#include <string>using namespace std;List::List(){    head=NULL;    _size=0;}List::List(const List& other){    head=NULL;    _size=0;    node* tem=other.head;    while(tem!=NULL){        push_front(tem->val);        tem=tem->next;    }}List::List(const string & num){    head=NULL;    _size=0;    int length=num.length();    for(int i=0;i<length;i++){        stringstream in;        in<<num[i];        int get;        in>>get;        push_front(get);    }}void List::clear(){    node* tem=head;    while(tem!=NULL){        node* next=tem->next;        delete tem;        tem=next;    }    head=NULL;    _size=0;}void List::push_front(int val){    node* newHead=new node(val,head);    head=newHead;    ++_size;}List List::operator+(const List& other){    List tem;    node* mytem=head;    node* othertem=other.head;    node* temtem=tem.head;    int U=0;    while(mytem!=NULL&&othertem!=NULL){        int up=0;        int val=mytem->val+othertem->val+U;        if(val>=10){            up=1;            val-=10;        }        //push_back        if(temtem==NULL)            temtem=tem.head=new node(val);        else{            temtem->next=new node(val);            temtem=temtem->next;        }        ++tem._size;        U=up;        mytem=mytem->next;        othertem=othertem->next;    }    while(mytem!=NULL){        int up=0;        int val=mytem->val+U;        if(val>=10){            up=1;            val-=10;        }        //push_back        if(temtem==NULL)            temtem=tem.head=new node(val);        else{            temtem->next=new node(val);            temtem=temtem->next;        }        U=up;        ++tem._size;        mytem=mytem->next;    }    while(othertem!=NULL){        int up=0;        int val=othertem->val+U;        if(val>=10){            up=1;            val-=10;        }        //push_back        if(temtem==NULL)            temtem=tem.head=new node(val);        else{            temtem->next=new node(val);            temtem=temtem->next;        }        U=up;        ++tem._size;        othertem=othertem->next;    }    if(U){        temtem->next=new node(U);        ++tem._size;    }    return tem;}List& List::operator=(const List& other){    clear();    node* tem=other.head;    node* temtem=head;    while(tem!=NULL){        //push_back        if(temtem==NULL)            temtem=head=new node(tem->val);        else{            temtem->next=new node(tem->val);            temtem=temtem->next;        }        ++_size;        tem=tem->next;    }    return *this;}int List::size() const{    return _size;}List::~List(){    clear();}ostream& operator<<(ostream & os, const List & me){    int out[me._size];    int i=0;    List::node* tem=me.head;    while(tem!=NULL){        out[i++]=tem->val;        tem=tem->next;    }    for(int i=me._size-1;i>=0;i--)        os<<out[i];    return os;}