C :

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

char same[256][256], def[256][256], done[256];
char op[100], lhs, rhs;
int i,j,k,m,n,c;

issame(int a, int b) {
   int i,r;
   if (same[a][b] == 1) return 1;
   if (same[a][b] == -1) return 0;
   if (isupper(def[a][0])) return issame(def[a][0],b);
   if (isupper(def[b][0])) return issame(a,def[b][0]);
   if (def[a][0] != def[b][0]) return 0;
   if (def[a][0] != 's') return 1;
   same[a][b] = same[b][a] = 1;
   for (i=1;(def[a][i] && def[b][i]) && issame(def[a][i],def[b][i]);i++);
   r = !def[a][i] && !def[b][i];
   same[a][b] = same[b][a] = r-1;
   return r;
}
   
   

main(){
   for (c=0;strcmp(op,"--");c++) {
      if (c) {
         printf("\n"); 
         memset(same,0,sizeof(same)); 
         memset(def,0,sizeof(def));
         memset(done,0,sizeof(done));
      }
      def['i'][0] = 'i'; def['c'][0] = 'c'; def['r'][0] = 'r';
      for (n=0;(1 == scanf("%s",op)) && *op != '-';n++) {
         assert(!strcmp(op,"type"));
         scanf(" %c = %c%*[a-z(]",&lhs,&rhs);
         def[lhs][0] = rhs;
         if (rhs == 's') {
            for (j=1;scanf(" %c",&def[lhs][j]) && def[lhs][j] != ')';j++);
            def[lhs][j] = 0;
         }
      }

      for (i='A';i<='Z';i++) {
         if (!def[i][0] || done[i]) continue;
         printf("%c",i);
         for (j=i+1;j<='Z';j++) {
            if (done[j]) continue;
            if (issame(i,j)) {
               assert(issame(j,i));
               printf(" %c",j);
               done[j] = 1;
            } else assert(!issame(j,i));
         }
         printf("\n");
      }
   }
}