duomem.cpp

操作系统的一次大作业,处理简单优先的程序

#include "iostream.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"

#define max 10
struct princple
{
	char left;
	char right[4];
};
typedef struct 
{
	char element[max];
	int top;
}stack;
stack *s;
int yxjz[8][8]={0,0,0,0,0,0,0,3,
0,0,2,1,0,1,0,3,
0,2,0,0,0,2,0,3,
0,0,1,1,2,1,0,3,
0,3,0,0,0,3,0,3,
0,3,0,0,0,3,2,3,
0,3,0,0,0,3,0,3,
1,1,1,1,1,1,1,3};

struct princple p[4]={{'S',"bAb"},{'A',"(B"},{'A',"a"},{'B',"Aa)"}};

char inputs[10],tem[5],string[10];
int i=0,j1=0,j=0;

void main()
{
	void ctable();
	void suanfa();
	ctable();
	cout<<"enter the stream(以$号结束):"<<endl;
	cout<<"->";
	cin>>inputs;
	suanfa();
}

void ctable()
{
	void suanfa();
	int i,j;
	cout<<"模拟优先矩阵："<<endl;
	cout<<"              0-空关系       1－小于关系"<<endl;
	cout<<"              2－等于关系    3－大于关系 "<<endl;  
	cout<<endl;
	for(i=0;i<8;i++)
	{
		for(j=0;j<8;j++)
		   printf("%d       ",yxjz[i][j]);
		cout<<endl;
	}
}


void suanfa()
{
    void push(char x);
	int find1(char x);
	int find2(char x);
	void error();
	int guiyue(char ch[]);
	j=0;
	s=(stack *)malloc(sizeof(stack));
	s->top=-1;/*置空栈*/
    push('$');/*把$符与开始符入栈*/
	cout<<"栈\t"<<"输入\t"<<"句柄"<<"\t输出\t"<<endl;

	cout<<"$\t"<<inputs;
    do
	{
		i=s->top;
        int a=find1(s->element[i]);
		int b=find2(inputs[j]);
		if(yxjz[a][b]=='0')
			error();
		if(yxjz[a][b]=='1'||yxjz[a][b]=='2')
		{
			push(inputs[j]);
			i++;
			j++;
		}
		if(yxjz[a][b]=='3')
		{
			int k;
			j1=i;
			while(yxjz[s->element[j1]][i]=='2')
				j1--;
			for(k=j1;k<=i;k++)
				string[k]=s->element[k];
			int hui=guiyue(string);
			s->top=j1;
			i=s->top;
			push(p[hui].left);
			for(k=0;k<=s->top;k++)
				cout<<s->element[k];
			cout<<"\t";
			for(k=j;k<10;k++)
				cout<<inputs[k];
			cout<<"\t";
			cout<<string<<"\t";
			cout<<p[hui].left<<"->"<<p[hui].right<<endl;

		}
		
	}while(!(s->element[s->top]=='E'&&s->element[s->top-1]=='$'&&inputs[j]=='$'));

}

void push(char x)
{
	s->top++;
	s->element[s->top]=x;
}

int find1(char x)
{
	if(x=='S')
		return 0;
	else if(x=='b')
		return 1;
	else if(x=='A')
		return 2;
	else if(x=='(')
		return 3;
	else if(x=='B')
		return 4;
    else if(x=='a')
		return 5;
	else if(x==')')
		return 6;
	else if(x=='$')
		return 7;
	else
		return NULL;
}
int find2(char x)
{
	if(x=='S')
		return 0;
	else if(x=='b')
		return 1;
	else if(x=='A')
		return 2;
	else if(x=='(')
		return 3;
	else if(x=='B')
		return 4;
    else if(x=='a')
		return 5;
	else if(x==')')
		return 6;
	else if(x=='$')
		return 7;
	else
		return NULL;
}

void error()
{
	cout<<"error!"<<endl;
	exit(0);
}
int guiyue(char ch[])
{
	if(strcmp(ch,"bAb")==0)
      return 0;
	else if(strcmp(ch,"(B")==0)
      return 1;
	else if(strcmp(ch,"a")==0)
      return 2;
	else if(strcmp(ch,"Aa)")==0)
      return 3;
	else
		return NULL;
}