Basics of C++

1)What are the different storage classes in C?
Ans=>C has three types of storage: automatic, static and allocated.
          Variable having block scope and without static specifier have
           automatic storage duration.
          Variables with block scope, and with static specifier have static scope.
          Global variables (i.e, file scope) with or without the static specifier also
           have static scope.
2) How are pointer variables initialized?
Ans=>Pointer variable are initialized by one of the following two ways
          Static memory allocation
          Dynamic memory allocation

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Worst Fit Memory Management Scheme

worst fit memory management program in c++
#include<iostream.h>
#include<conio.h>
#include<stdio.h>
class WFMM
{ int a[50],c,par,i,j,n,p[50],d[50],r,s,b,m,min,g;
 public:   
        void input();
        void output();
}X;
void WFMM::input()
{
 c=1000;
 r=c;
 cout<<"Total memory Available = 1000";
 cout<<"\nEnter the number of partition that you want in memory\t";
 cin>>par;
 cout<<"\nEnter the size of remaining partitions";
 cout<<"\n\nRemaining Memory=\t1000";
 for(i=0;i<par;i++)
 {
   if(r!=0)
   {
    cout<<"\n Partition "<<i+1<<"\t";
    cin>>s;
    r=r-s;
    a[i]=s;
    cout<<"\n Remaining Memory="<<r;
   }
 }
 cout<<"\n\nEnter the number of processes\t";
 cin>>n;
 cout<<"\nEnter the size of processes\n";
 for(i=0;i<n;i++)
 {
  cout<<"\nP["<<i+1<<"] =\t";
  cin>>p[i];
 }
}
void WFMM::output()
{
 for(i=0;i<n;i++)
 {min=0;
  for(j=0;j<n;j++)
  {
   if(p[i]<=a[j])
   {m=a[j]-p[i];
    if(m>min)
    {min=m;
     d[i]=j+1;
    }
   }
  }
  g=d[i]-1;
  a[g]=a[g]-p[i];
 }
 cout<<"\n\nThe Process allocation are as Follows\n";
 cout<<"\nProcess\tPartition";
 for(i=0;i<n;i++)
  cout<<"\n P["<<i+1<<"]\t "<<d[i];
}
  main()
{

 X.input();
 X.output();
 getch();
}

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Best Fit Memory Management Scheme

We can also allocate memory locations to dofferent processes using best fit memory management scheme.Here is the code in C++
#include<iostream.h>
#include<conio.h>
#include<stdio.h>
class BFMM
{ int a[50],c,par,i,j,n,p[50],d[50],r,s,b,m,min,g;
 public:   
        void input();
        void output();
}X;
void BFMM::input()
{
 c=1000;
 r=c;
 cout<<"Total memory Available = 1000";
 cout<<"\nEnter the number of partition that you want in memory\t";
 cin>>par;
 cout<<"\nEnter the size of remaining partitions";
 cout<<"\n\nRemaining Memory=\t1000";
 for(i=0;i<par;i++)
 {
   if(r!=0)
   {
    cout<<"\n Partition "<<i+1<<"\t";
    cin>>s;
    r=r-s;
    a[i]=s;
    cout<<"\n Remaining Memory="<<r;
   }
 }
 cout<<"\n\nEnter the number of processes\t";
 cin>>n;
 cout<<"\nEnter the size of processes\n";
 for(i=0;i<n;i++)
 {
  cout<<"\nP["<<i+1<<"] =\t";
  cin>>p[i];
 }
}
void BFMM::output()
{
 for(i=0;i<n;i++)
 {min=1000;
  for(j=0;j<n;j++)
  {
   if(p[i]<=a[j])
   {m=a[j]-p[i];
    if(m<min)
    {min=m;
     d[i]=j+1;
    }
   }
  }
  g=d[i]-1;
  a[g]=a[g]-p[i];
 }
 cout<<"\n\nThe Process allocation are as Follows\n";
 cout<<"\nProcess\tPartition";
 for(i=0;i<n;i++)
  cout<<"\n P["<<i+1<<"]\t "<<d[i];
}
  main()
{

 X.input();
 X.output();
 getch();
}

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First Fit Memory Management

we can use first fit memory management scheme to allocate memory space to different processes.Here is the program in c++
#include<iostream.h>
#include<conio.h>
#include<stdio.h>
class FFMM
{ int a[50],c,par,i,j,n,p[50],d[50],e[50],r,s,b;
 public:   
        void input();
        void output();
}X;
void FFMM::input()
{
 c=1000;
 r=c;
 cout<<"Total memory Available = 1000";
 cout<<"\nEnter the number of partition that you want in memory\t";
 cin>>par;
 cout<<"\nEnter the size of remaining partitions";
 cout<<"\n\nRemaining Memory=\t1000";
 for(i=0;i<par;i++)
 {
   if(r!=0)
   {
    cout<<"\n Partition "<<i+1<<"\t";
    cin>>s;
    r=r-s;
    a[i]=s;
    cout<<"\n Remaining Memory=\t"<<r;
   }
 }
 cout<<"\n\nEnter the number of processes\t";
 cin>>n;
 cout<<"\nEnter the size of processes\n";
 for(i=0;i<n;i++)
 {
  cout<<"\nP["<<i+1<<"] =\t";
  cin>>p[i];
 }
}
void FFMM::output()
{
 for(i=0;i<n;i++)
 {
  for(j=0;j<n;j++)
  {
   if(p[i]<=a[j])
   {
    d[i]=j+1;
    a[j]=a[j]-p[i];
    break;
   }
  }
 }
 cout<<"\n\nThe Process allocation are as Follows\n";
 cout<<"\nProcess\tPartition";
 for(i=0;i<n;i++)
  cout<<"\n P["<<i+1<<"]\t "<<d[i];
}
  main()
{

 X.input();
 X.output();
 getch();
}

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