calculate inverses

triangle.c

@@ -23,7 +23,7 @@ int generate_triangle_group(groupelement_t *group, int size, int k1, int k2, int
 {
 	queue_t q;
 	int id, n;
-	groupelement_t *cur;
+	groupelement_t *cur, *inv;
 
 	int k[3] = {k1, k2, k3};
 
@@ -57,5 +57,15 @@ int generate_triangle_group(groupelement_t *group, int size, int k1, int k2, int
 		}
 	}
 
+	for(int i = 0; i < size; i++) {
+		cur = &group[i];
+		inv = &group[0];
+		while(cur->parent && inv) {
+			inv = inv->adj[cur->letter];
+			cur = cur->parent;
+		}
+		group[i].inverse = inv;
+	}
+
 	return n;
 }