Use -std=c++20 for day 15

fwcd · fwcd · commit b1d2cc2f8334 · 2024-12-15T19:02:15.000+01:00
diff --git a/day15/derivation.nix b/day15/derivation.nix
@@ -5,7 +5,7 @@
 
     buildPhase = ''
       mkdir -p out
-      $CXX -o out/day15 day15.cpp
+      $CXX -o out/day15 -std=c++20 day15.cpp
     '';
 
     installPhase = ''
