UDP server client in c

Server

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>

int main()
{
        int sock;
        int addr_len, bytes_read;
        char recv_data[1024],send_data[1024];
        struct sockaddr_in server_addr , client_addr;


        if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
            perror("Socket");
            exit(1);
        }

        server_addr.sin_family = AF_INET;
        server_addr.sin_port = htons(5000);
        server_addr.sin_addr.s_addr = INADDR_ANY;
        bzero(&(server_addr.sin_zero),8);


        if (bind(sock,(struct sockaddr *)&server_addr,
            sizeof(struct sockaddr)) == -1)
        {
            perror("Bind");
            exit(1);
        }

        addr_len = sizeof(struct sockaddr);

        printf("\nUDPServer Waiting for client on port 5000");
        fflush(stdout);

        int count = 0,i;
        char a[20][10],d[20][10];
        strcpy(a[0],"A");
        strcpy(a[1],"B");
        strcpy(a[2],"C");
        strcpy(a[3],"D");
        strcpy(d[0],"123");
        strcpy(d[1],"124");
        strcpy(d[2],"100");
        strcpy(d[3],"99");

        while (1)
        {

          bytes_read = recvfrom(sock,recv_data,1024,0,
                            (struct sockaddr *)&client_addr, &addr_len);


          recv_data[bytes_read] = '\0';

          printf("\n(%s , %d) said : ",inet_ntoa(client_addr.sin_addr),
                                       ntohs(client_addr.sin_port));
          printf("%s", recv_data);
          printf("SEND : ");
         // gets(send_data);

             int p = 0;
                 for(i=0;i<4;i++)
                 {
                        if(strcmp(recv_data,d[i]) == 0)
                        {
                             strcpy(send_data,a[i]);p=1;
                        }
                 }
                 if(p == 0)
                 strcpy(send_data,"No one on that role.");

          sendto(sock,send_data,strlen(send_data),0,(struct sockaddr *)&client_addr,sizeof(struct sockaddr));

          fflush(stdout);

        }
        return 0;
}

CLIENT

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>

int main()
{
int sock,bytes_recv,sin_size;
struct sockaddr_in server_addr;
struct hostent *host;
char send_data[1024],recv_data[1024];

host= (struct hostent *) gethostbyname((char *)"127.0.0.1");


if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
{
perror("socket");
exit(1);
}

server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(5000);
server_addr.sin_addr = *((struct in_addr *)host->h_addr);
bzero(&(server_addr.sin_zero),8);
sin_size = sizeof(struct sockaddr);

   while (1)
   {

    printf("Type Something (q or Q to quit):");
    gets(send_data);

    if ((strcmp(send_data , "q") == 0) || strcmp(send_data , "Q") == 0)
       break;

    else
       sendto(sock, send_data, strlen(send_data), 0,
              (struct sockaddr *)&server_addr, sizeof(struct sockaddr));

         bytes_recv = recvfrom(sock,recv_data,1024,0,(struct sockaddr *)&server_addr,&sin_size);
          recv_data[bytes_recv]= '\0';
     printf("Received :%s\n",recv_data);
   }

}