diff --git a/.common/cpp/skeleton.cpp b/.common/cpp/skeleton.cpp
index 2699a76..d836ae2 100644
--- a/.common/cpp/skeleton.cpp
+++ b/.common/cpp/skeleton.cpp
@@ -20,11 +20,9 @@ std::ostream &operator<<(std::ostream &s, std::pair<T, U> const &p) {
 
 namespace helpers {
 
-using namespace std;
-
 namespace math {
 
-static constexpr int32_t MODULO = 1000000007;
+static constexpr std::int32_t MODULO = 1000000007;
 
 long pow(long base, long exp) {
   if (exp == 0) return 1;
@@ -56,27 +54,22 @@ namespace output {
 
 template <typename T>
 inline void answer(const T &ans) {
-  cout << ans << "\n";
+  std::cout << ans << "\n";
 }
 
-inline void yes() { cout << "YES\n"; }
-inline void no() { cout << "NO\n"; }
-
-inline void yesno(bool ans) {
-  if (ans) {
-    yes();
-  } else {
-    no();
-  }
-}
+inline void yes() { std::cout << "YES\n"; }
+inline void no() { std::cout << "NO\n"; }
+inline void yesno(bool ans) { std::cout << (ans ? "YES" : "NO") << "\n"; }
 
 }  // namespace output
 
+using namespace std;
+
 using namespace math;
 using namespace input;
 using namespace output;
 
-#define LOOP(n) for (auto i = 0; i < n; ++i)
+#define LOOP(var, n) for (auto var = 0; var < n; ++var)
 
 }  // namespace helpers