[数据结构与算法]数据结构-单链表的一元稀疏多项式

放一下关于一元稀疏多项式-链表版
与去年的一元稀疏多项式·数组版（点击跳转）构成联动

我的代码：

#include<bits/stdc++.h>
using namespace std;
//一元稀疏多项式版本三
typedef struct Node{
    double data_coef;//存系数
    int data_expn;//存指数
    Node *next;
}Node,*LinkList;

int list_empty(LinkList &L){//链表空返回1
    if(L)return 0;//非空
    else return 1;
}

void show_list(LinkList &L){
    //展示链表内的元素
    cout<<"[list]:"<<endl;
    if(list_empty(L)){
        cout<<"Empty!"<<endl;
        return;
    }else{
        LinkList p;
        p=L->next;
        while(p!=NULL){
            cout<<"coef: "<<p->data_coef<<"  expn: "<<p->data_expn<<endl;
            p=p->next;
        }
    }
}

void read(LinkList &L,int num){
    int n;
    LinkList p;
    cout<<"【Please input the items of poly】:";
    cin>>n;
    while(n--){
    	p=(LinkList)malloc(sizeof(Node));
        cin>>p->data_coef>>p->data_expn;
        if(num==0)p->data_coef=-p->data_coef;
        p->next=L->next;
        L->next=p; 
    }
	show_list(L);
}

void read_result_list(LinkList &L){
	LinkList p=new Node;
	p=L->next;
    cout<<"[list]:";
    if(list_empty(p)){
        cout<<"Empty!"<<endl;
        return;
    }else{//对于指数为0时不应该输出指数
    	if(p->data_expn==0)cout<<p->data_coef;
        else if(p->data_expn==1)cout<<p->data_coef<<"X";
        else cout<<p->data_coef<<"X^"<<p->data_expn;
        p=p->next;
        while(p){
            if(p->data_coef>0)cout<<"+";
            if(p->data_expn==0)cout<<p->data_coef;
            else if(p->data_expn==1)cout<<p->data_coef<<"X";//为了避免出现负指数时
            else cout<<p->data_coef<<"X^"<<p->data_expn;
            p=p->next;
        }
    }
}

void deal(LinkList &A,LinkList &B){
    //Pa=Pa+Pb
    LinkList qa;
    LinkList qb;
    LinkList qc;
    qc=A;//qc是一个中间节点，便于两链表之间的节点转换 
    qa=A;
    qb=B->next;

    while(qa&&qb){
		if(qa->next&&qa->next->data_expn<qb->data_expn){
            qc=qb->next;
			qb->next=qa->next;
			qa->next=qb;
            qa=qa->next;
            qb=qc;
            continue;
        }
		if(qa->next&&qa->next->data_expn>qb->data_expn){
			qa=qa->next;continue;
		}
        if(qa->data_expn==qb->data_expn){
            double sum=0;
			sum=qa->data_coef + qb->data_coef;//1是加法  
            if (sum==0){
                LinkList s=new Node;s=qa;qa=qa->next;free(s);
                s=qb;qb=qb->next;free(s);
            }else{ 
                qa->data_coef=sum;; 
                qa=qa->next; 
                LinkList s=new Node;
				s=qb;qb=qb->next;free(s);//删除pb中元素结点 
        	}
        	continue;
    	}
	}
	if(qb)qa->next=qb;//假如qb还有多的元素结点，直接接后面，但感觉 
	free(B);
}


int main(){
	//初始化 
	LinkList a=new Node;//式1
	a->next=NULL;
    LinkList b=new Node;//式2
	b->next=NULL;

	int num;
    cout<<"welcome use."<<endl;
    cout<<"【add】   - 1"<<endl<<"【minus】 - 0"<<endl<<"【PLS input:】";
    cin>>num;    
    read(a,1);
    read(b,num);
	deal(a,b);
    read_result_list(a);
	return 0;
}