#include <stdio.h>

static const char* la[]= {"sa1","sa2","sa3",NULL};
static const char* lb[]= {"sb1","sb2",NULL};

static const char** arr[]= {la,lb,NULL};

int main() {
  const char **i;
  const char ***j;
  for (j=arr; *j;++j)
    for (i=*j; *i; ++i) printf("%s\n",*i);
  return 0;
}