Compilare: main.cpp: In function 'int main()': main.cpp:34:21: warning: loop variable '<structured bindings>' creates a copy from type 'const std::pair<int, int>' [-Wrange-loop-construct] 34 | for (auto const [e, v] : G[u]) { | ^~~~~~ main.cpp:34:21: note: use reference type to prevent copying 34 | for (auto const [e, v] : G[u]) { | ^~~~~~ | &