public StudentRecord Delete(int key)
{
int h = hash(key);
int location = h;
for (int i = 1; i < m; i++)
{
if (array[location] == null)
{
return(null);
}
if (array[location].getstudentId() == key)
{
StudentRecord temp = array[location];
array[location].setstudentId(-1);
n--;
return(temp);
}
location = (h + i) % m;
}
return(null);
}
public void Insert(StudentRecord newRecord)
{
int key = newRecord.StudentId;
int h = hash(key);
int location = h;
for (var i = 1; i < m; i++)
{
if (array[location] == null || array[location].StudentId == -1)
{
array[location] = newRecord;
n++;
return;
}
if (array[location].StudentId == newRecord.StudentId)
{
throw new InvalidOperationException("Duplicate Key");
}
location = (h + i) % m;
}
Console.WriteLine("Table is full: Record cannot be inserted.");
}
static void Main(string[] args)
{
int id, choice;
String name;
Write("Enter initial size of table: ");
int size = Convert.ToInt32(ReadLine());
HashTable table = new HashTable(size);
while (true)
{
WriteLine("1. Insert a Record");
WriteLine("2. Search a Record");
WriteLine("3. Delete a Record");
WriteLine("4. Display Table");
WriteLine("5. Exit");
Write("Enter your choice: ");
choice = Convert.ToInt32(ReadLine());
if (choice == 5)
{
break;
}
switch (choice)
{
case 1:
Write("Enter student ID: ");
id = Convert.ToInt32(ReadLine());
Write("Enter student name: ");
name = ReadLine();
StudentRecord aRecord = new StudentRecord(id, name);
table.Insert(aRecord);
break;
case 2:
Write("Enter a key to be searched: ");
id = Convert.ToInt32(ReadLine());
aRecord = table.Search(id);
if (aRecord == null)
{
WriteLine("Key not Found");
}
else
{
WriteLine(aRecord.ToString());
}
break;
case 3:
Write("Enter a key to be deleted: ");
id = Convert.ToInt32(ReadLine());
table.Delete(id);
break;
case 4:
table.DisplayTable();
break;
}
}
}