通过链表实现的多项式乘法【C++】

被某喵发给我让我看的代码丑到哭。。。。就随手再写一个吧。。。

话说最近一直在用C＃。突然换回C++好不爽。竟然有点嫌弃C++了。。。

废话不多说。直接上代码吧。基本没有注释。不过挺水的也挺好理解。

哦对。题目是这样的。。。

#include<iostream>using namespace std;struct Term{Term *Pre, *Next;int Exp;double Coef;};class polynomial{public:Term *Head,*Tail;polynomial();~polynomial();void Add(double Coef, int Exp);void Sort();void Merge();void inputPoly();void outputPoly();friend const polynomial operator*(const polynomial& polyA, const polynomial& polyB);private:};polynomial::polynomial(){Head = new Term;Head->Pre = nullptr;Head->Coef = 0;Head->Exp = 1;Head->Next = NULL;Tail = Head;}polynomial::~polynomial(){}void polynomial::Add(double Coef, int Exp){Term *term = new Term;term->Pre = Tail;term->Coef = Coef;term->Exp = Exp;term->Next = NULL;Tail->Next = term;Tail = term;}void polynomial::inputPoly(){double coef;int exp;cout << "请输入多项式的系数和指数，当指数过小（小于-99）时将自动结束输入" << endl;while (true){cin >> coef >> exp;if (exp < -99){break;}this->Add(coef, exp);}this->Merge();}void polynomial::outputPoly(){Term *Current = Head;bool First = true;cout << "多项式为：";while (Current->Next != NULL){Current = Current->Next;if (First){First = false;if (Current->Coef != 1){if (Current->Exp == 0){cout << "1";}else if (Current->Exp == 1){cout << Current->Coef << "x";}else{cout << Current->Coef << "x^" << Current->Exp;}}else{if (Current->Exp == 0){cout << "1";}else if (Current->Exp == 1){cout << "x";}else{cout << "x^" << Current->Exp;}}}else{if (Current->Coef > 0){if (Current->Coef != 1){if (Current->Exp == 0){cout << "+" << Current->Coef;}else if (Current->Exp == 1){cout << "+" << Current->Coef << "x";}else{cout << "+" << Current->Coef << "x^" << Current->Exp;}}else{if (Current->Exp == 0){cout << "+" << Current->Coef;}else if (Current->Exp == 1){cout << "+" << "x";}else{cout << "+" << "x^" << Current->Exp;}}}else{if (Current->Coef != -1){if (Current->Exp == 0){cout << Current->Coef;}else if (Current->Exp == 1){cout << Current->Coef << "x";}else{cout << Current->Coef << "x^" << Current->Exp;}}else{if (Current->Exp == 0){cout << Current->Coef;}else if (Current->Exp == 1){cout << "-x";}else{cout << "-x^" << Current->Exp;}}}}}cout << endl;}//按指数排序void polynomial::Sort(){double tempCoef;int tempExp;int ActionNum = 0;do{Term *Current = Head;ActionNum = 0;while (Current->Next != NULL){Current = Current->Next;if (Current->Next == NULL){break;}if (Current->Exp > Current->Next->Exp){tempCoef = Current->Coef;Current->Coef = Current->Next->Coef;Current->Next->Coef = tempCoef;tempExp = Current->Exp;Current->Exp = Current->Next->Exp;Current->Next->Exp = tempExp;ActionNum++;}}} while (ActionNum > 0);}//合并多项式void polynomial::Merge(){this->Sort();Term *Current = Head;bool Action = false;while (Current->Next != NULL){if (!Action){Current = Current->Next;}Action = false;if (Current->Next == NULL){Tail = Current;break;}if (Current->Exp == Current->Next->Exp){Current->Coef = Current->Coef + Current->Next->Coef;if (Current->Next->Next == NULL){Current->Next = NULL;Tail = Current;break;}else{Current->Next->Next->Pre = Current;Current->Next = Current->Next->Next;}Action = true;if (Current->Coef == 0){Term *temp = Current->Next;Current->Next->Pre = Current->Pre;Current->Pre->Next = Current->Next;Current = temp;}}if (Current->Next == NULL){Tail = Current;}}}//*运算符重载polynomial const operator*(const polynomial& polyA, const polynomial& polyB){polynomial polyC;Term *CurrentA = polyA.Head;Term *CurrentB = polyB.Head;while (CurrentA->Next != NULL){CurrentB = polyB.Head;CurrentA = CurrentA->Next;while (CurrentB->Next != NULL){CurrentB = CurrentB->Next;polyC.Add(CurrentA->Coef * CurrentB->Coef, CurrentA->Exp + CurrentB->Exp);}}polyC.Merge();return polyC;}int main(){polynomial ah,bh,ch;ah.inputPoly();ah.outputPoly();bh.inputPoly();bh.outputPoly();ch = ah * bh;ch.outputPoly();system("pause");return 0;}