diff --git a/.common/cpp/skeleton.cpp b/.common/cpp/skeleton.cpp
index efcfe86..6f4ee9e 100644
--- a/.common/cpp/skeleton.cpp
+++ b/.common/cpp/skeleton.cpp
@@ -2,6 +2,17 @@
 
 namespace {
 
+using namespace std;
+
+long pow(long base, long exp) {
+  if (exp == 0)
+    return 1;
+  long half = pow(base, exp / 2);
+  if (exp % 2 == 0)
+    return half * half;
+  return half * half * base;
+}
+
 void solve() {
   // TODO
 }