Thread: structures

ok,i'm trying to build a program, with socket connections. but i'm having difficulties in structures.
i can't figure out the problem of this code.
it brings me Segmation Fault after gcc compiling.
i hope you will help me with this.

Code:

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

struct topics {
 int topicID;
 char *baseTopicName;
 struct messages* thema;
} staticTopics[6];

struct messages {
  char *topicName;
  char *sender;
  char *message;

};

int main(){
     staticTopics[1].thema[1].topicName="aasss";


   
}