minipentium.cpp

此程序实现一定的小心pc功能

#include<iostream.h>

enum Type{NUM,MOV,ADD,SUB,MUL,EMPTY};

class exp
{
public:
	Type kind;
	int number;
	exp * left;
	exp * right;
	exp();	
};
exp :: exp()
{
	kind = EMPTY;
	number = 0;
	left = NULL;
	right = NULL;
}

void initExp(int a,exp * x)
{
	exp * temp = x;
	temp->kind = NUM;
	temp->number = a;
	temp->left = NULL;
	temp->right = NULL;
}

exp MOVL(exp a,exp b)
{
	exp c;	
	c.kind = MOV;
	c.left = new exp();
	*(c.left) = a;
	c.right = new exp();
	*(c.right) = b;
	return c;
}

exp ADDL(exp a,exp b)
{
	exp c;
	if((a.kind == EMPTY)||(b.kind == EMPTY))
	{
		cout<<"ERROR!"<<endl;
		return c;
	}
	
	c.kind = ADD;
	c.left = new exp();
	*(c.left) = a;
	c.right = new exp();
	*(c.right) = b;
	return c;
}

exp SUBL(exp a,exp b)
{
	exp c;
	if((a.kind == EMPTY)||(b.kind == EMPTY))
	{
		cout<<"ERROR!"<<endl;
		return c;
	}
	
	c.kind = SUB;
	c.left = new exp();
	*(c.left) = a;
	c.right = new exp();
	*(c.right) = b;
	return c;
}

exp MULL(exp a,exp b)
{
	exp c;
	if((a.kind == EMPTY)||(b.kind == EMPTY))
	{
		cout<<"ERROR!"<<endl;
		return c;
	}
	
	c.kind = MUL;
	c.left = new exp();
	*(c.left) = a;
	c.right = new exp();
	*(c.right) = b;
	return c;
}

void print(exp * a)
{	
	if(a->kind == EMPTY)
	{
		return ;
	}

	
	if((a->left == NULL)&&(a->right == NULL))
	{
		cout<<"NUM :  "<<a->number<<endl;
		return;
	}

	if(a->left != NULL)
		print(a->left);
	if(a->kind == MOV)
		cout<<"MOV"<<endl;
	else if(a->kind == ADD)
		cout<<"ADD"<<endl;
	else if(a->kind == SUB)
		cout<<"SUB"<<endl;
	else if(a->kind == MUL)
		cout<<"MUL"<<endl;

	if(a->right != NULL)
		print(a->right);
	
}

void getNum(exp * a)
{
	
	if(a->kind == NUM)
	{
		cout<<"NUM : "<<a->number<<endl;
		return ;
	}
	if(a->left != NULL)
		getNum(a->left);
	if(a->right != NULL)
		getNum(a->right);
}
int main()
{
	//令 x = 1 , y = 2 ,构造 x + y
	exp x0;
	exp y0;
	initExp(1,&x0);
	initExp(2,&y0);
	exp x;
	exp y;
	exp z;

	x = MOVL(x0,x);
	y = MOVL(y0,y);
	y = ADDL(x,y);

	cout<<"AST中的各节点为："<<endl;
	print(&y);
	cout<<endl;

	cout<<"算式中的数字有："<<endl;
	getNum(&y);
	cout<<endl;
	
	return 0;
}