VB.NET CODE USING GRIDVIEW AND ACCESS DATABASE

Imports System.Data
Imports System.Data.OleDb

Public Class MAIN
    Public connString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=GAURAV_DATABASE.mdb"
    Public OleDBConn1 As System.Data.OleDb.OleDbConnection = New System.Data.OleDb.OleDbConnection(connString)
    Public SQLString As String
    Public OleDbDataAdapter1 As New OleDbDataAdapter()
    Public DataSet1 As New DataSet()
    Public cb As New OleDb.OleDbCommandBuilder()
    'myConnection = new SqlConnection("server=(local)\VSdotNET;Trusted_Connection=yes;database=northwind")
    ' da = new SqlDataAdapter("Select * from Customers", thisConnection)
    'Public thisConnection As New SqlConnection("server=(local);Trusted_Connection=yes;database=GAURAV_DATABASE.mdb")
    'Public cb As New SqlCommandBuilder()
    'Public da As New SqlDataAdapter()
    'Public SqlCommand1 As New SqlCommand()
    '' Sql Query
    'Public sql As String = "SELECT * FROM IMPORTANT"
    '' Create a Command
    '' Create SqlDataAdapter
    ''da = New SqlDataAdapter
    ''da.SelectCommand = SqlCommand1

    Private Sub BTN_EXIT_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTN_EXIT.Click
        login.Close()
        Me.Close()
    End Sub

    Private Sub MAIN_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        'If InputBox("ENTER PASSWORD:", "GAURAV DETAILS", "**********") <> "vikas" Then
        '    MessageBox.Show("INCORRECT PASSWORD!!!!!!!", "GAURAV DETAILS", MessageBoxButtons.OK, MessageBoxIcon.Error)
        '    Me.Close()
        'End If
        'Dim myConnection As OleDbConnection = New OleDbConnection
        'myConnection.ConnectionString = connString
        '' create a data adapter
        'Dim da As OleDbDataAdapter = New OleDbDataAdapter("Select * from IMPORTANT", myConnection)

        'Dim ds As DataSet = New DataSet
        'da.Fill(ds, "Customers")
        'DATA_GRID.DataSource = ds.DefaultViewManager
        '  Dim ConnString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=MyMDB.mdb"
        '  OleDBConn1.Open()
    End Sub

    Private Sub BTN_IMPORTANT_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTN_IMPORTANT.Click
        DataSet1.Clear()
        SQLString = "SELECT * FROM IMPORTANT"
        OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()
        OleDbDataAdapter1.Fill(DataSet1, "IMPORTANT")
        DATA_GRID.DataSource = DataSet1.Tables("IMPORTANT")
        'OleDBConn1.Close()
        cb = New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)

        'Dim sql As String = "SELECT * FROM IMPORTANT"
        'SqlCommand1 = New SqlCommand(sql, thisConnection)
        'da = New SqlDataAdapter
        'da.SelectCommand = SqlCommand1
        'cb = New SqlCommandBuilder(da)
        'da.Fill(DataSet1, "IMPORTANT")
        'DATA_GRID.DataSource = DataSet1.Tables("IMPORTANT")
        'DATA_GRID.SetDataBinding(DataSet1, "IMPORTANT")
        'Try
        '    da = New SqlDataAdapter("select * from IMPORTANT", thisConnection)
        '    'da.SelectCommand = New SqlCommand()
        '    'da.SelectCommand.Connection = thisConnection
        '    'da.SelectCommand.CommandText = "select * from IMPORTANT"
        '    'da.SelectCommand.CommandType = CommandType.Text
        '    thisConnection.Open()
        '    cb = New SqlCommandBuilder(da)
        '    ' Set the MissingSchemaAction property to AddWithKey because Fill will not cause primary
        '    ' key & unique key information to be retrieved unless AddWithKey is specified.
        '    da.MissingSchemaAction = MissingSchemaAction.AddWithKey
        '    da.Fill(DataSet1, "IMPORTANT")
        '    DATA_GRID.DataSource = DataSet1.Tables("IMPORTANT")
        '    'DATA_GRID.AutoGenerateColumns = True
        '    'DATA_GRID.DataSource = DataSet1
        '    'DATA_GRID.DataMember = "IMPORTANT"
        '    thisConnection.Close()
        'Catch ex As Exception
        '    MessageBox.Show(ex.ToString)
        'End Try
    End Sub

    Private Sub BTN_INVESTMENT_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTN_INVESTMENT.Click
        DataSet1.Clear()
        SQLString = "SELECT * FROM INVESTMENTS"
        OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()
        OleDbDataAdapter1.Fill(DataSet1, "INVESTMENTS")
        DATA_GRID.DataSource = DataSet1.Tables("INVESTMENTS")
        cb = New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)
        ' OleDBConn1.Close()
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Try
            '   Dim cb As New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)
            ' DataSet1.Tables("IMPORTANT").Rows(0).Item(1) = "vvvvvvvvv"
            'DataSet1.Tables("IMPORTANT").Rows(0).Item(2) = "99999999"
           
            OleDbDataAdapter1.Update(DataSet1, DATA_GRID.DataSource.ToString)
        Catch ex As Exception
            MessageBox.Show(ex.ToString)
        End Try
        MessageBox.Show("UPDATE " & DATA_GRID.DataSource.ToString & " DATABASE")


        'SQLString = "UPDATE TABLE INVESTMENTS"
        'OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()

        'DATA_GRID.DataSource = DataSet1.Tables(0)
        'MessageBox.Show(DataSet1.Tables(1).ToString)
        ' DATA_GRID.DataSource = DataSet1.Tables("IMPORTANT")
        ' OleDbDataAdapter1.Update(DataSet1)
        ' OleDbDataAdapter1.InsertCommand = New OleDbCommand("Insert into IMPORTANT (ID,NAME,PH) VALUES()", OleDBConn1)
        ' OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        ' OleDbDataAdapter1.Update(DataSet1)
        'DATA_GRID.DataSource = DataSet1.Tables(" IMPORTANT")
        'OleDBConn1.Close()
    End Sub

    Private Sub BTN_REMINDERS_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTN_REMINDERS.Click
        DataSet1.Clear()
        SQLString = "SELECT * FROM REMINDERS"
        OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()
        OleDbDataAdapter1.Fill(DataSet1, "REMINDERS")
        DATA_GRID.DataSource = DataSet1.Tables("REMINDERS")
        cb = New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)
    End Sub

    Private Sub BTN_VAULT_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTN_VAULT.Click
        DataSet1.Clear()
        SQLString = "SELECT * FROM VAULT"
        OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()
        OleDbDataAdapter1.Fill(DataSet1, "VAULT")
        DATA_GRID.DataSource = DataSet1.Tables("VAULT")
        cb = New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)
    End Sub

    Private Sub BTN_BANKING_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTN_BANKING.Click
        DataSet1.Clear()
        SQLString = "SELECT * FROM BANKING"
        OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()
        OleDbDataAdapter1.Fill(DataSet1, "BANKING")
        DATA_GRID.DataSource = DataSet1.Tables("BANKING")
        cb = New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)
    End Sub

    Private Sub BTN_PLANS_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTN_PLANS.Click
        DataSet1.Clear()
        SQLString = "SELECT * FROM PLANS"
        OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()
        OleDbDataAdapter1.Fill(DataSet1, "PLANS")
        DATA_GRID.DataSource = DataSet1.Tables("PLANS")
        cb = New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        DataSet1.Clear()
        SQLString = "SELECT * FROM CONTACTS"
        OleDbDataAdapter1 = New OleDbDataAdapter(SQLString, OleDBConn1)
        'OleDBConn1.Open()
        OleDbDataAdapter1.Fill(DataSet1, "CONTACTS")
        DATA_GRID.DataSource = DataSet1.Tables("CONTACTS")
        cb = New OleDb.OleDbCommandBuilder(OleDbDataAdapter1)
    End Sub
End Class

Singly Link List : C code

#includestdio.h
#includeconio.h
#includealloc.h
#includestdlib.h
struct s_ll
{
 int x;
 struct s_ll *nxt;

} *ll;

void append(struct s_ll **, int);
void in_begin(struct s_ll **, int);
void del(struct s_ll **, int);
void in_middle(struct s_ll **, int, int);
int count(struct s_ll *);
void display(struct s_ll *);

void main()
{
 int i=2;
 int j=2;
 int ch,num,loc;

 ll=NULL;
 clrscr();
 printf("PRESS ENTER ");

 getch();
 clrscr();
 for(i=1;i<20;i++)
 {
 gotoxy(i,j);
  printf("*");
  j++;

 }
  for(;i<39;i++)
 {
 j--;
 gotoxy(i,j);
 printf("*");

 }
     getch();
 clrscr();

  gotoxy(0,0);
  printf("****** MAIN MENU ***********\n");
  printf("1. READ A FILE\n");
  printf("2. WRITE A FILE\n");
  printf("3. XXXXXXXXXXXXX\n");
  printf("4. YYYYYYYYYYYYY\n");
  printf("****************************\n");



 getch();


 do
 {
  clrscr();
  gotoxy(0,0);
  printf("******** PROGRAM TO IMPLEMENT SINGLY nxt LIST ***********\n");
  printf("-----------------------------------------------------------\n");
  printf("1. CREATE OR APPEND\n");
  printf("2. INSERT AT START\n");
  printf("3. INSERT AT MIDDLE\n");
  printf("4. DELETE A NODE\n");
  printf("5. COUNT NODE\n");
  printf("6. DISPLAY NODE\n");
  printf("7. EXIT\n");
  printf("***********************************************************\n");

  oper:
  printf("ENTER CHOICE (1-6)/7 FOR EXIT - ");
  scanf("%d",&ch);

 switch(ch)
 {
   case 1:
    char res;
    do {
      printf("ENTER ANY NUMBER : ");
      scanf("%d",&num);
      append(&ll,num);
      printf("ENTER AGAIN (y/n) : ");
      fflush(stdin);
      res=getchar();

    } while(res != 'n');
    break;
case 2:
printf("Enter The x : ");
scanf("%d",&num);
in_begin(&ll,num);
break;
case 3:
printf("\nEnter The Position :");
scanf("%d",&loc);
printf("\nEnter The x : ");
scanf("%d",&num);
in_middle(&ll,loc,num);
break;
case 4:
printf("\nEnter The x u Want To Delete : ");
scanf("%d",&num);
del(&ll,num);
break;
case 5:
printf("\nThe No Of s_lls Are %d",count(ll));
getch();
break;
case 6:
display(ll);
getch();
break;
case 7:
printf("\n\nQuiting.......");
getch();
exit(0);
break;
default:
printf("Invalid choice.Please Enter Correct Choice");
//goto oper;
 }

 }while(ch != 7);



}

void append(struct s_ll **q,int num)
{ struct s_ll *temp,*r;
temp = *q;
if(*q==NULL)
{ temp = (struct s_ll *)malloc(sizeof(struct s_ll));
temp->x=num;
temp->nxt=NULL;
*q=temp;
}
else
{ temp = *q;
while(temp->nxt !=NULL)
{ temp=temp->nxt;
}
r = (struct s_ll *)malloc(sizeof(struct s_ll));
r->x=num;
r->nxt=NULL;
temp->nxt=r;
}
}
void display(struct s_ll *q)
{ if(q==NULL)
{ printf("\n\nEmpty nxt List.Can't Display The x");
getch();
goto last;
}
while(q!=NULL)
{ printf("\n%d",q->x);
q=q->nxt;
}
last:
}

int count(struct s_ll *q)
{ int c=0;
if(q==NULL)
{ printf("Empty nxt List.\n");
getch();
goto last;
}
while(q!=NULL)
{ c++;
q=q->nxt;
}
last:
return c;
}

void in_begin(struct s_ll **q,int num)
{ struct s_ll *temp;
if(*q==NULL)
{ printf("nxt List Is Empty.Can't Insert.");
getch();
goto last;
}
else
{ temp=(struct s_ll *)malloc(sizeof(struct s_ll));
temp->x=num;
temp->nxt=*q;
*q=temp; /* pointing to the first s_ll */
}
last:
getch();
}

void in_middle(struct s_ll **q,int loc,int num)
{ struct s_ll *temp,*n;
int c=1,flag=0;
temp=*q;
if(*q==NULL)
{ printf("\n\nnxt List Is Empty.Can't Insert.");
getch();
goto last;
}
else
while(temp!=NULL)
{ if(c==loc)
{ n = (struct s_ll *)malloc(sizeof(struct s_ll));
n->x=num;
n->nxt=temp->nxt;
temp->nxt=n;
flag=1;
}
c++;
temp=temp->nxt;
}
if(flag==0)
{ printf("\n\ns_ll Specified Doesn't Exist.Cant Enter The x");
getch();
}
else
{ printf("x Inserted");
getch();
}
last:
getch();
}
void del(struct s_ll**q,int num)
{ if(*q==NULL)
{ printf("\n\nEmpty nxted List.Cant Delete The x.");
getch();
goto last;
}
else
{
struct s_ll *old,*temp;
int flag=0;
temp=*q;
while(temp!=NULL)
{ if(temp->x==num)
{ if(temp==*q) /* First s_ll case */
*q=temp->nxt; /* shifted the header s_ll */
else
old->nxt=temp->nxt;
free(temp);
flag=1;
}
else
{ old=temp;
temp=temp->nxt;
}
}
if(flag==0)
printf("\nx Not Found...");
else
printf("\nx Deleted...Tap a key to continue");
getch();
}
last:
getch();
}