操作系统实验_银行家算法

#include<iostream>
using namespace std;
#define W 10
#define R 2
#define MAXPROCESS 50 /*最大进程数*/
#define MAXRESOURCE 100 /*最大资源数*/
int ALL_RESOURCE[W];
char name[MAXPROCESS][10];
int available[MAXRESOURCE]; /*可用资源数组*/
//int max[MAXPROCESS][MAXRESOURCE]; /*最大需求矩阵*/
int maxneed[100][100];
int allocation[MAXPROCESS][MAXRESOURCE]; /*分配矩阵*/
int need[MAXPROCESS][MAXRESOURCE]; /*需求矩阵*/
int request[MAXPROCESS][MAXRESOURCE]; /*进程需要资源数*/
bool finish[MAXPROCESS]; /*系统是否有足够的资源分配*/
int p[MAXPROCESS]; /*记录序列*/
int i_name= 0;
char nameList[MAXPROCESS][10];
int numOfPro,numOfSource; /*m个进程,n 个资源*/
//------------------------------------------------------------------------
void Init()
{
cout << "进程数目:" << endl;
cin >> numOfPro;
cout << "资源数目:" << endl;
cin >> numOfSource;
for(int i=0; i<numOfPro ;++ i)
{
cout << "第"<< i+1<<"进程名称：" << endl;
cin >> name[i];
cout << "第"<< i+1<<"进程所需各个资源的最大数目：" << endl;
for (int j =0; j <numOfSource ;++ j )
{
cin >> maxneed[i][j] ;
}
}
for(int i=0; i<numOfPro ;++ i)
{
cout << "第"<< i+1<<"进程所需已经分配的各类资源数目：" << endl;
for (int j =0; j <numOfSource ;++ j )
{
cin >> allocation[i][j ] ;
need[i][j] = maxneed[i][j] - allocation[i][j];
request[i][j] = need[i][j];
}
}
cout << "输入当前可提供的各类资源数目:" << endl;
for(int i=0;i<numOfSource;++ i)
{
cin >> available[i];
}
}
void Add(int a[] ,int b[] , int n )
{
for (int i=0;i<n ;++ i)
{
a[i] += b[i];
}
}
//---------------------------------------------------------------
---------
int Islittle(int a[] ,int b[],int n)
{
for (int i=0;i<n ;++ i)
{
if (a[i] > b[i])
return 0;
}
return 1;
}
void Safe()
{
int nowPro = 0 ;
while(1)
{
int i = 0;
for ( i = 0;i<numOfPro;++ i)
{
if (false == finish[i] && Islittle(need[i], available,numOfPro))
{
nowPro = i;
break;
}
}
if (numOfPro == i)
{
for (int j= 0;j<numOfPro;++ j)
{
if ( false == finish[j])
{
cout << "没有安全序列" << endl;
return ;
}
}
cout << "安全序列为：" <<endl;
for (int j=0; j<numOfPro;++ j)
{
cout << name[p[j]]<<"->" ;
}cout << endl;
return ;
}
finish[nowPro] = true;
Add(available, allocation[nowPro],numOfPro);
p[i_name ++ ] = i;
}
}
int main()
{
Init();
Safe();
return 0 ;
}
//------------------------------------------------------------------------
实验结果。