(ALT 2) QUIZ II Operating System (CLIENT)

// LINK SOAL : https://www.dropbox.com/sh/wussgfrqrmazf9g/AADnp_e-zKkHZWXyAFDQ5yJFa?dl=0
// LINK TEMPLATE : http://pastebin.com/Rc7A08xG

#include <stdio.h>
#include <sys/ipc.h>
#include <sys/types.h>
#include <sys/sem.h>
#include <sys/shm.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <ctype.h>

struct data{
    char nama[25];
    char cc[17];
    float sale;
};

int main(){
    struct sembuf s;
    int h=shmget(123456,sizeof(struct data),IPC_CREAT|0666);
    int e=semget(123456,1,IPC_CREAT|0666);
    semctl(e,0,SETVAL,0);
    struct data *card=(struct data *)shmat(h,NULL,0666);
    int i,flag=0;
    printf("/=================================\\\n");
    printf("|Blue Jack Card Processing System |\n");
    printf("\\=================================/\n\n");
    printf("Client\n------\n");
    do{
        do{
            flag=0;
            printf("Input cardholder name [5..20][starts with Mr /Ms ]['exit' to quit'] : ");
            scanf("%[^\n]",card->nama);getchar();fflush(stdin);
            if(strstr(card->nama,"Mr")!=0||strstr(card->nama,"Ms")!=0)
                flag=1;
            if(strcasecmp(card->nama,"exit")==0)
                break;
            //printf("%s",strstr(card->nama,"Mr"));
        }while(flag==0);
        if(strcasecmp(card->nama,"exit")!=0){
            do{
                flag=0;
                printf("Input card number[16 digits|must be number] : ");
                scanf("%[^\n]",card->cc);getchar();fflush(stdin);
                for(i=0;i<strlen(card->cc);i++){
                    if(!isdigit(card->cc[i]))
                        flag=1;
                }
                if(strlen(card->cc)!=16)
                    flag=1;
            }while(flag==1);
            do{
                flag=0;
                printf("Input sale amount [100...7500] : $");
                scanf("%f",&card->sale);getchar();fflush(stdin);
                if(card->sale>=100&&card->sale<=7500)
                    flag=1;
            }while(flag==0);
        }
        s.sem_num=0;
        s.sem_op=1;
        s.sem_flg=0;
        semop(e,&s,1);
        printf("Confirm Order, Press Enter\n");
        getchar();
    }while(strcasecmp(card->nama,"exit")!=0);
    shmdt(&s);
    shmctl(h,IPC_RMID,0);
    semctl(e,0,IPC_RMID);
    return 0;
}