#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct node {
        int value;
        struct node * next;}node_t;

node_t* addHead(){

    node_t* h = malloc(sizeof(node_t));
    if(h == NULL) return NULL;
    h->value=1;
    h->next=NULL;
    return h;
}
void addNode (int val,node_t* head)
{
    node_t * newNode =NULL;
    newNode = malloc(sizeof(node_t));
    if(newNode==NULL) return;
    newNode->value=val;
    newNode->next=NULL;
    while(head->next!=NULL)
        head=head->next;
    head->next=newNode;
}
void printNodes (node_t* head)
{
    if(head==NULL)return;
    while(head)
    {
        printf("%d ",head->value);
        head=head->next;
    }
    printf("\n");
}
void removeNode(int val,node_t* head)
{
    node_t * second;
    second = head->next;
    node_t * third;
    third = second->next;

    while(third){
         if(second->value==val)
        {
            head->next=third;
            free(second);
            return;
        }
        head=second;
        second=head->next;
        third=second->next;
    }
    if(second->value==val)
    {
        head->next=NULL;
        free(second);
        return;
    }


}
node_t* removeHead(node_t* head){
    node_t * second;
    second=head;
    head=head->next;
    free(second);
    return head;
}


int main()
{
    node_t * head;
    head=addHead();
    addNode(5,head);
    addNode(7,head);
    printNodes(head);
    head=removeHead(head);
    addNode(9,head);
    addNode(10,head);
    addNode(2,head);
    removeNode(7,head);
    printNodes(head);
    return 0;
}