Create, insert, delete, and invert a single-chain table

/*-----------------------------------------------------*/
/* Create, insert, delete, and invert a single-chain table -----------*/
/* ------------ Written by redfire250 ----- 2005.5.10 ----*/
/*-----------------------------------------------------*/
# Include <malloc. h>
# Include <stdio. h>
# Define null 0
Struct student
{
Long number;
Char name [20];
Long score;
Struct student * next;
};
Int n = 0;/* n is the global variable used to calculate the number of nodes in the linked list */
/*-----------------------------------------*/
/* -------------- Create the node function creat ()--------*/
/*-----------------------------------------*/
Struct student * creat ()
{
Struct student * P1;
Struct student * P2;
Struct student * head = NULL;
P1 = P2 = (struct student *) malloc (sizeof (struct student);/* open up an available memory unit */
Printf ("Please input the student's number name and the score: \ n ");
Scanf ("% LD % S % lD", & p2-> Number, P2-> name, & p2-> score );
While (P2-> number! = 0)
{
N ++;
If (n = 1)/* indicates whether the first node is opened */
Head = P2;
Else
P1-> next = P2;
P1 = P2;
P2 = (struct student *) malloc (sizeof (struct student ));
Printf ("input the number the name and the score: \ n ");
Scanf ("% LD % S % lD", & p2-> Number, P2-> name, & p2-> score );
}
P1-> next = NULL;
Return (head );
}
/*------------------------------------------*/
/* -------------- View the linked list content function view ()------*/
/*------------------------------------------*/
View (struct student * head)
{
Struct student * P;
P = head;
While (p-> next! = NULL)
{
Printf ("% LD % S % LD \ n", p-> Number, p-> name, p-> score );
P = p-> next;
}
Printf ("% LD % S % LD \ n", p-> Number, p-> name, p-> score );
}
/*-------------------------------------------------*/
/* -------------- Insert node function (inserted before) insert ()-------*/
/*-------------------------------------------------*/
Insert (struct student * head, int num)/* head is the head pointer of the linked list, And num is inserted into the position of the linked list */
{
Int T = 1;
Struct student * P1, * P2;
P1 = head;
If (Num> N | num <0)
{
Printf ("input error !!! \ N ");
Return 0;
}
While (T <Num-1)/* Find the previous node to insert the node */
{
P1 = p1-> next;
T ++;
}
P2 = (struct student *) malloc (sizeof (struct student ));
Printf ("input the number the name and the score: \ n ");
Scanf ("% LD % S % lD", & p2-> Number, P2-> name, & p2-> score );
P2-> next = p1-> next;
P1-> next = P2;
N ++;
}
/*------------------------------------------*/
/* ------------ Delete the node function delnode ()--------*/
/*-----------------------------------------*/
Delnode (struct student * head, int node)
{
Int T = 1;
Struct student * P1, * P2;
P2 = head;
If (node> N | node <1)
{
Printf ("error !!! The node is not exist! ");
Return 0;
}
While (T <node-1)/* Find the previous node of the node to be deleted */
{
P2 = P2-> next;
T ++;
}
P1 = P2-> next;/* Find the last node to be deleted */
Free (P2-> next);/* release the Node space to be deleted (delete )*/
P2-> next = p1;/* point the previous node to the next node */
N --;
}
/*-------------------------------------------------*/
/* -------------- Reverse reorganization of the linked list invert ()-------*/
/*-------------------------------------------------*/
Struct student * invert (struct student * head)
{
Struct student * P1, * P2;
P1 = head;
P2 = p1-> next;
Head = P2-> next;
P1-> next = NULL;
While (Head-> next! = NULL)
{
P2-> next = p1;
P1 = P2;
P2 = head;
Head = head-> next;
}
Head-> next = P2;
P2-> next = p1;
Return head;
}
Main ()
{
Int number1, number2;
Struct student * head;
Head = creat ();
View (head );
Printf ("the n that you want to insert: \ n ");
Scanf ("% d", & number1 );
Insert (Head, number1 );
View (head );
Printf ("the node that you want to delete: \ n ");
Scanf ("% d", & number2 );
Delnode (Head, number2 );
View (head );
Printf ("Inverte the list: \ n ");
View (invert (head ));
Getch ();
}