优化了平衡，尤其对于向后倾倒的几种极限情况进行优化

Shibo-main-TOMMY/lib/ArduinoJson/extras/tests/MixedConfiguration/use_double_0.cpp

@@ -0,0 +1,17 @@
+#define ARDUINOJSON_USE_DOUBLE 0
+#include <ArduinoJson.h>
+
+#include <catch.hpp>
+
+TEST_CASE("ARDUINOJSON_USE_DOUBLE == 0") {
+  DynamicJsonDocument doc(4096);
+  JsonObject root = doc.to<JsonObject>();
+
+  root["pi"] = 3.14;
+  root["e"] = 2.72;
+
+  std::string json;
+  serializeJson(doc, json);
+
+  REQUIRE(json == "{\"pi\":3.14,\"e\":2.72}");
+}