diff --git a/libnum/include/num/vec.h b/libnum/include/num/vec.h
index b5e9443..ffd375e 100644
--- a/libnum/include/num/vec.h
+++ b/libnum/include/num/vec.h
@@ -161,6 +161,16 @@ inline constexpr vec<T,N> &operator/=(vec<T,N> &lhs, T const &rhs) {
     return lhs;
 }
 
+template<typename T, int N>
+inline constexpr vec<T,N> operator+(vec<T,N> const &lhs) {
+    return lhs;
+}
+template<typename T, int N>
+inline constexpr vec<T,N> operator-(vec<T,N> lhs) {
+    for(int i = 0; i < N; i++)
+        lhs[i] = -lhs[i];
+    return lhs;
+}
 template<typename T, int N>
 inline constexpr vec<T,N> operator+(vec<T,N> lhs, vec<T,N> const &rhs) {
     return lhs += rhs;