cpp

It is actually better to make variable assignmets using the list notation double d {2.2} as it protects us from conversions that lose information such as int i = 7.2 // i is now 7. The = operator for assignment is actually outdated and mantained only for C compatibility!

Range-for-statement

for (auto x:v)
cout << x << endl;

More efficient

for (auto& x:v)
cout << x << endl;