#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct record{
    char name[64];
    int number;
    struct record *next;
    
}student;

    student *addContact(student *list);
    student *viewContact(student *list);
    student *searchContact(student *list);
    student *deleteAll(student *list);
    
main(){
    student *ptr, *head=NULL; int option = 0, k;
    
    while(option!=5){

printf("\n M E N U \n[1] Add Contact\n[2] View Contact\n[3] Search Contact\n[4] Delete All Contact\n[5] Exit\nOption: ");
    
    scanf("%i",&option);
    
    switch(option){
        case 1: head = addContact(head);
            break;
        
        case 2: head = viewContact(head);
            break;
    
        case 3: head = searchContact(head);
            break;
                    
        case 4: head = deleteAll(head);
            break;
        
        case 5:
            exit(1);
        
        default: printf("\nInvalid Option!\n\n");
    }
    }
}
    student * addContact(student * list){
        student * new;
    
    new = (student *) malloc(sizeof(student));
    
    printf("\nName: ");    scanf("%s", new->name);
    printf("Number: ");    scanf("%i", &new->number);
    
    new->next = list;
    return new;
}
    student * viewContact(student * list){
        student * ptr = list;
        if(NULL==ptr){
            printf("\nNOTHING to view\n");
        }else{
            printf("\nCONTACTS\n");
            while(NULL!=ptr){
                printf("Name: %s\nNumber: %i\n",ptr->name, ptr->number);
                ptr = ptr->next;
            }
        }
        return list;
}
    student * searchContact(student * list){
        student * ptr = list;
        
        printf("search for: ");
        scanf("%s", ptr);
        
	while(ptr){
             if(strcmp(ptr->next,ptr)>0)
	     return ptr;
	     ptr=ptr->next;
	     }
	     return NULL;
             //printf("NO DATA FOUND\n");
        //}else{
           //printf("\nName: %s Number: %d\n", ptr->name,ptr->number);
           //ptr = ptr->next;
        //}            
}
    
    
    student * deleteAll(student * list){
        student * ptr = list;
        
        while(ptr){
            list = ptr->next;
            free(ptr);
            ptr = list;
        }
        return NULL;
}

student * searchContact(student * list){
    student * p = head;

    printf("search for: %s\n", list->name);

    while(p){
        if(strcmp(p->name, list->name) == 0)
            return p;
        p = p->next;
    }
    return NULL;
}