Make tree visualization more compact

ConflictSet.cpp

@@ -676,6 +676,9 @@ void lastLeqMulti(Arena &arena, Node *root, std::span<Key> keys,
     explicit DebugDotPrinter(FILE *file) : file(file) {}
 
     void print(Node *node) {
+      if (node->child[0] == nullptr && node->child[1] == nullptr) {
+        return;
+      }
       for (int i = 0; i < 2; ++i) {
         if (node->child[i] != nullptr) {
           fprintf(file, " k_%.*s -> k_%.*s;\n", node->len,
@@ -702,11 +705,11 @@ void lastLeqMulti(Arena &arena, Node *root, std::span<Key> keys,
     for (auto iter = extrema(node, false); iter != nullptr;
          iter = next(iter, true)) {
       fprintf(file,
-              " k_%.*s [label=\"k=\\\"%.*s\\\" "
+              " k_%.*s [label=\"k=\\\"%.*s\\\"\\n"
 #if SHOW_PRIORITY
-              "p=%u "
+              "p=%u\\n"
 #endif
-              "m=%d v=%d r=%d\"];\n",
+              "m=%d\\nv=%d r=%d\"];\n",
               iter->len, (const char *)(iter + 1), iter->len,
               (const char *)(iter + 1),
 #if SHOW_PRIORITY