solve hw-9

hws/tiktok_trends/StringPtrUtils.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include <string>
+#include <functional>
+
+struct StringPtrHash {
+    size_t operator()(const std::string* s) const {
+        return std::hash<std::string>()(*s);
+    }
+};
+
+struct StringPtrEqual {
+    bool operator()(const std::string* a, const std::string* b) const {
+        if (a == b) return true;
+        if (!a || !b) return false;
+        return *a == *b;
+    }
+};