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

int main(int argc, char **argv)
{
  int sock,n;
  struct sockaddr_in addr,in;
  char buff[4096];
  int len=sizeof(in);
	
  if ( ( sock = socket(AF_INET, /*TODO*/, IPPROTO_UDP) ) < 0 ) {
    perror("socket");
    exit(1);
    }

  /*TODO*/
  //Fill in addr struct
   
  if ( bind(/*TODO:socket*/, (struct sockaddr *) /*TODO:addr*/, sizeof(addr)) < 0 ) {
    perror("bind");
    exit(1);
  }
  
for ( ; ; ) {
    n = recvfrom(/*TODO:socket*/, /*TODO: buffer*/, 4096, 0, (struct sockaddr *)&in, &len);
	if (n < 0) {
	    perror("recvfrom error");
	    exit(-1);
	}
    buff[n]=0;
	printf("Received packet from %s:%d\nData: %s\n\n",inet_ntoa(in.sin_addr), ntohs(in.sin_port), buff);

	snprintf(buff,sizeof(buff),"%d\n",(int)strlen(buff)-1);
	n = sendto(/*TODO: socket*/, /*TODO:buffer*/, strlen(buff), 0, (struct sockaddr *)&in, sizeof(in));
	if (n < 0) {
	    perror("sendto error");
	    exit(-1);
	}
  }
}