new coord stuff from 09

lib/include/aocpp/Coord.hpp

@@ -41,8 +41,16 @@ auto CCW(Coord) -> Coord;
 
 auto Turn180(Coord) -> Coord;
 
+/// @brief Computes the "1 norm" of a coordinate as a vector
+/// @param  vector
+/// @return Sum of magnitudes of components
 auto Norm1(Coord) -> std::int64_t;
 
+/// @brief Computes the "infinity norm" of a coordinate as a vector
+/// @param  vector
+/// @return Magnitude of the largest component
+auto NormInf(Coord) -> std::int64_t;
+
 /// Add two coordinates pairwise
 auto operator+(Coord, Coord) -> Coord;
 

lib/src/Coord.cpp

@@ -73,6 +73,10 @@ auto Norm1(Coord c) -> std::int64_t {
   return std::abs(c.x) + std::abs(c.y);
 }
 
+auto NormInf(Coord c) -> std::int64_t {
+  return std::max(std::abs(c.x), std::abs(c.y));
+}
+
 auto operator+(Coord a, Coord b) -> Coord {
   return {a.x + b.x, a.y + b.y};
 }