Skip to main content

Interactive C program to implement Instert begining, delete begining and reversing of single linked list

shiv@ubuntu:~/ds/list$ cat   revlist.c
/*
 * Interactive C program to simulate following operations
 * on single linked list
 * 1. insert begining of the list
 * 2. display data in the list (traversing)
 * 3. delete element at begining of the list
 * 4. reverse the elements in single linked list
 */

#include<stdio.h>
#include<stdlib.h>
struct list
{
int data;
struct list *next;
};
typedef struct list *L;

/* function to insert element into list */

void insert(L *head)
{
 /* look for typedef temp is pointer not variable,
  *  same will apply to all
  */
 L temp;

 temp=malloc(sizeof(struct list));
 if(!temp) {
    printf("Can't allocate memory\n");
    return;
 }

 printf("Enter element to insert\n");
 scanf("%d", &temp->data);
 temp->next = NULL;

 if(*head == NULL) {
    *head = temp;
 } else {

    temp->next = *head;
    *head = temp;
 }
}

/* function to display elements in the list */

void display(L head)
{
  L temp;
  
  temp = head;
  if(temp == NULL){
     printf("Empty list \n");
     return;
  }

 printf("List elements are \n");
 while(temp) {
     printf("%d\n", temp->data);
     temp = temp->next;
 }

}

/* function to delete elements in the list */

void del(L *head)
{
  L temp;

 if(*head == NULL) {
    printf("No elements to delete, Empty list\n");
    return;
 }

 temp =*head;
 printf("Element deleted %d\n", temp->data);
 *head =(*head)->next;
 /* release the memory once deleted */
 free(temp);

}

/* function to reverse elements in list */

void reverse(L *head)
{
  L temp, t, rev=NULL;
  temp = *head;
 
  while(temp != NULL) {
        t = temp;
        /* first we need to move the list before modifying it */
        temp = temp->next;
        t->next = rev;
        rev  = t;
  }

  /* change head to point reversed list */
  *head =rev;
}


/* Main function to help test list operations */

int main()
{
 L head = NULL;
 int ch;

 while(1) {
 system("clear");
 printf("1 Insert\n2 Display\n3 del\n4 reverse\n5 exit\n");
 printf("Enter your choice\n");
 scanf("%d", &ch);
 switch(ch) {
    case 1: insert(&head); break;
    case 2: display(head); break;
    case 3: del(&head); break;
    case 4: reverse(&head); break;
    case 5: exit(0);
    default: printf("Invalid choice\n");
 }
 getchar();
 getchar();
}
return 0;
}
/* end of  the program */
Labels:

Comments

Post a Comment

Popular posts from this blog

C Program to Simulate Linux Cat command

/*  * C program to Simulate Implementation of  Linux *cat* command  * This program will not handle redirection  * you can try to improve this program to handle redirection of file contents  */ #include<stdio.h> #include<string.h> #define MAX_FILE_NAME_CHARS 255 int main(int argc, char *argv[]) {  FILE *fp;  char file_name[MAX_FILE_NAME_CHARS], ch;  int i;  /*   * after creating a.out, rename it as mycat for our own cat command   * and it usage is same as standard cat command   */  if(argc<1){     printf("Usage mycat <filename> \n");     return 0;  }  /*   * cat handles more than one file   * so we need this loop to handle all the files provided   * on command line   */  for(i=1; i<=argc;i++){     /* no need of copy but for understanding purpose, i have created      * string for each file name      */     strncpy(file_name, argv[i], MAX_FILE_NAME_CHARS);     fp=fopen(file_name, "r");     if(fp == NULL) {   
4 comments
Read more

simple program to create Orphan process

shiv@ubuntu:~/ds/unix$ cat  orp.c /*  * Program to create orphan process @ Linux  * getpid() gives process PID and   * getppid() gives process's parent ID   * here main() process ID is parent id is current shells PID  * once process becomes orphan it is adopted by init process(it's PID is 1)  */   #include<stdio.h> #include<unistd.h> int main() {  pid_t p; /* create child process */  p=fork();  if(p==0) {     /* fork() returns Zero to child */     sleep(10);  }  printf("The child process pid is %d parent pid %d\n", getpid(), getppid()); /*parent/child waits for 20 secs and exits*/  sleep(20);  printf("\nProcess %d is done its Parent pid %d...\n", getpid(), getppid());  return 0; } O/p shiv@ubuntu:~/ds/unix$ ./a.out The child process pid is 2575 parent pid 1922 The child process pid is 2576 parent pid 2575 Process 2575 is done its Parent pid 1922... shiv@ubuntu:~/ds/unix$ Process 2576 is done its Parent pid 1...
3 comments
Read more

Interactive C program to implement stack using doubly linked list

shiv@ubuntu:~/ds/stack$ cat stack.c /*  * Copy right by Shiv Yaragatti  * you are free to use, modify  and redistribute code on own risk  * Interactive C Program to implement STACK using Doubly linked list  */ #include "header.h" struct stack { int data; struct stack *next; struct stack *prev; }; typedef struct stack *S; /*Push elements in to stack */ void push(S *stack) {   int e;   S temp;   temp=malloc(sizeof(struct stack));   if(!temp){      printf("Can't allocate memory\n");      return;  }  printf("Enter element to push\n");  scanf("%d", &e);  temp->data=e;  if(*stack == NULL){     temp->next = temp->prev = NULL;     *stack=temp;  } else {    temp->next = *stack;    (*stack)->prev = temp;    temp->prev = NULL;    *stack=temp;  } } /* Display elements in the stack */ void display(S s){    S temp;    temp=s;    printf("Elements are ...\n");    while(temp) {     printf("%d\n", temp->data
Post a Comment
Read more