#include
#include
#include?
#include
using?namespace?std;


//輔助函數?
bool?isDigit（const?char&?a）{
	if?（a?>=?48??&&?a?<=?57）?return?true;
	else?return?false;
}

int?toDigit（const?string&?c）{
	stringstream?a;
	int?b;
	a<	a>>b;
	return?b;
}

string?getexpression（const?string&?expression）{	
	int?i=0len=expression.length（）;
	while（?expression[i]?!=?‘=‘?）{
		i++;
	}
	return?expression.substr（i+1len-i）;
}

string?getName（const?string&?expression）{
	int?i=0;
	while（?expression[i]?!=?‘=‘?）{
		i++;
	}
	return?expression.substr（0i）;
}

bool?isRightfull（const?string&?expression）{
	int?len=expression.length（）-1;
	int?index=-1;
	for（int?i=len;?i>=0;）{
		int?a=0;
		if（?expression[i]?!=?‘）‘?）?return?false;
		else?{
			if（?!isDigit（expression[i-1]）?）
				?return?false;
			else{
				while（?isDigit（expression[i-a-1]）?）{
					a++;
				}
			}
			if（?index?>=?toDigit（?expression.substr（i-aa）?）?）?
				return?false;
			else?index?=?toDigit（?expression.substr（i-aa）?）;
			
			if（?expression[i-a-1]?!=?‘‘?）?return?false;
			else?{
				if（?!isDigit（expression[i-a-2]）?）
					return?false;
				while（?isDigit（expression[i-a-2]）?）{
					a++;
				}
				
				if?（?toDigit（?expression.substr（i-a-1a）?）?==?0?）
					return?false;
				if?（?expression[i-a-2]?==?‘-‘?）?a++;
				if?（?expression[i-a-2]?!=?‘（‘?）?return?false;
			}
		}
		i=i-a-3;
	}?
	return?true;
}



//單項式類?	
class?Item{
	private:
		int?coefficient;
		int?index;
	public:
		Item（）;
		int?getIndex（）?const;
		int?getCoefficient（）?const;
		void?setCoefficient（int?a）;
		void?setIndex（int?a）;
		Item?operator+（const?Item&?a）;
		Item?operator-（const?Item&?a）;
		Item?operator*（const?int&?a）;
		Item?operator*（const?Item&?a）;
		int?getValue（const?int&?a）;
		void?show_Item（）;
};


Item::Item（）{
	index=0;?coefficient=0;
}

int?Item::getIndex（）?const{
	return?index;
}

int?Item::getCoefficient（）?const{
	return?coefficient;
}

void?Item::setCoefficient（int?a）{
	coefficient=a;
}

void?Item::setIndex（int?a）{
	index=a;
}

Item?Item::operator+（const?Item&?a）{
	Item?b;?
	b.coefficient?=?a.coefficient?+?coefficient;
	b.index?=?index;
	return?b;
}
		
Item?Item::operator-（const?Item&?a）{
	Item?b;?
	b.coefficient?=?coefficient?-?a.coefficient;
	b.index?=?a.index;
	return?b;
}
		
Item?Item::operator*（const?int&?a）{
	Item?b;
	b.coefficient?=?coefficient?*?a;
	b.index?=?index;
	return?b;
}
		
Item?Item::operator*（const?Item&?a）{
	Item?b;
	b.coefficient?=?coefficient?*?a.coefficient;
	b.index?=?index?+?a.index;
	return?b;?
}?

int?Item::getValue（const?int&?a）{?
			return?coefficient?*?pow（?aindex?）;
		}
		
void?Item::show_Item（）{
	if（?index?==?0?）?cout<	else?{
		if（?index?!=?1?）{
			if（?coefficient?==?1??）?cout<<“x^“<			else?{
				if（?coefficient?==?-1?）?cout<<“-x^“<					else?cout<				}
		}
		else