c++实现链式存储结构实现一元多项式的加法运算

#include <iostream>
using namespace std;

struct Node
{
int coef;
int exp;
Node *next;
};

//初始化
void InitList(Node * &L)
{
L = new Node;
L->next = NULL;
L->coef = 0;
L->exp = 0;
}

//在多项式链表的第i个位置插入结点
void InsertNode(Node *& L, int c, int e, int i)
{
Node *p, *q; int j = 1;
q = new Node;
q->coef = c;
q->exp = e;
q->next = NULL;

p = L;
while (j <= i)
{
p = p->next;
++j;
}
q->next = p->next;
p->next = q;
}

//按指数非递减给多项式排序
void SortList(Node *&L)
{
Node *p, *q, *pre;
p = L->next;
L->next = NULL;
while (p != NULL)
{
if (L->next == NULL)       //处理第一个结点
{
L->next = p;
p = p->next;
L->next->next = NULL;
}
else         //处理剩余其他结点
{
pre = L;
q = pre->next;
while (q && q->exp < p->exp)
{
pre = q;
q = q->next;
}
q = p->next;
p->next = pre->next;
pre->next = p;
p = q;
}
}
}

void print(Node * L)
{
SortList(L);
Node *p;
p = L->next;
while (p != NULL)
{
cout << p->coef << "x^" << p->exp << "+";
p = p->next;
}
cout << endl;
}

Node *AddPoly(Node *L1, Node *L2)       //一元多项式相加
{
Node *pa, *pb, *s, *pc, *p;
Node *tc;    //创建尾节点
pc = new Node;
pc->next = NULL;    /*pc为新建单链表的头结点*/
tc = pc;   /*tc始终指向新建单链表的最后结点*/
pa = L1->next;
pb = L2->next;   //获得多项式单链表的第一个结点
while (pa != NULL && pb != NULL)    //pa,pb都不为空，就进行比较，否则，跳出while
{
if (pa->exp < pb->exp)         //将*pa结点复制到*s并链到pc尾
{
s = new Node;
s->coef = pa->coef;
s->exp = pa->exp;
s->next = NULL;
tc->next = s;
tc = s;
pa = pa->next;
}
else if (pa->exp > pb->exp)      //将*pb结点复制到*s并链到pc尾
{
s = new Node;
s->coef = pb->coef;
s->exp = pb->exp;
s->next = NULL;
tc->next = s;
tc = s;
pb = pb->next;
}
else         //pa->expn=pa->expn时的情况
{
if (pa->coef + pb->coef != 0)     //如果相加系数之和不为0，则将新结点插在tc后面
{
s = new Node;
s->coef = pa->coef + pb->coef;
s->exp = pa->exp;
s->next = NULL;
tc->next = s;
tc = s;
}
pa = pa->next;   //跳过当前的结点，继续后面的结点的比较
pb = pb->next;
}
}
//将尚未扫描完的余下结点复制并链接到pc单链表之后
if (pa != NULL)        //pb为空
p = pa;
else                  //pa为空
p = pb;
while (p != NULL)
{
s = new Node;
s->coef = p->coef;
s->exp = p->exp;
s->next = NULL;
tc->next = s;
tc = s;
p = p->next;
}
return pc;
}

int main()
{
int c1[] = { 3, 7, 9, 5 }, c2[] = { 8, 22, -9 };
int e1[] = { 2, 1, 8, 7 }, e2[] = { 9, 0, 8 };

Node *la, *lb, *lc; int k;
InitList(la);
InitList(lb);
InitList(lc);
for (k = 0; k < 4; k++)
InsertNode(la, c1[k], e1[k], k);
for (k = 0; k < 3; k++)
InsertNode(lb, c2[k], e2[k], k);
cout << "多项式A：";
print(la);
cout << "多项式B：";
print(lb);

cout << "多项式相加的结果为：" << endl;
lc = AddPoly(la, lb);
print(lc);

return 0;

}