#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct element
{
    char client[20];
    struct element *next;
} nod;

nod *adaugaClient(nod *prim, char *client)
{
    nod *nou = (nod *)malloc(sizeof(nod));
    strcpy(nou->client, client);
    nou->next = NULL;
    if (prim == NULL)
        return nou;
    nod *q = (nod *)malloc(sizeof(nod));
    for (q = prim; q->next != NULL; q = q->next);
    q->next = nou;
    return prim;
}
void arataclienti(nod *prim)
{
    nod *q = (nod *)malloc(sizeof(nod));
    for (q = prim; q!= NULL; q = q->next)
        printf("%s ", q->client);
}
nod *retragerecerere(nod *prim,char *client)
{   nod *aux=(nod *)malloc(sizeof(nod));
    nod *nou = (nod *)malloc(sizeof(nod));
    nou = prim;
    while(nou->next->client!=client)
    if(nou->next==NULL)
    return prim;

    aux=nou->next;
    nou->next=nou->next->next;
    if(aux)
    free(aux);
    return nou;
}
nod *stergeclient(nod *prim)
{
    nod *nou = (nod *)malloc(sizeof(nod));
    nou = prim->next;
    if(prim)
    free(prim);
    return nou;
}
int aux=0;
int main()
{
 nod *prim = NULL;
    char o,nume[20];
    int val;
    while(aux==0)
   {
       printf("\n");
       printf("a : Adaugare client \n");
       printf("s : Stergere client \n");
       printf("l : Listare clienti \n");
       printf("r : Retrage client \n");
       printf("t : Termina programul \n");

       printf("\nOptiunea:  ");
       while(isspace(o=getchar()) );
       printf("\n");
       if (!isspace(o))
          switch (tolower(o))
         {

         case 'a': {  printf("Nume client: ");
             scanf("%s", &nume);
             prim = adaugaClient(prim,nume);
             break;}
         case 's':{
                      prim = stergeclient(prim);
             break;}
         case 'l':{  puts("\nClientii sunt:");
             arataclienti(prim);
             break;}
         case 'r':{
              scanf("%s", &nume);
                prim = retragerecerere(prim,nume);

         break;}
         case 't':
             aux=1;
         default:
             printf("Eroare : Comanda inexistenta\n");
         }
   }
    return 0;
}