Compiler Explorer
Compiler Explorer; sometimes referred to as Godbolt (after its creator Matthew Godbolt) is an online compiler for C++. It is good for testing and prototyping small code snippets from C++ across many different compiler versions, from different vendors and on different architectures.
It also displays the assembly output allowing you to have a closer look at what goes on under the hood in C++. It also allows sharing permalinks to instances of Godbolt with specific code and configuration running so you xan distribute working code to anyone as long as they got a browser.
Godbolt ⚡
Head on over to Compiler Explorer and copy the "Hello World" program into the editor window. It should automatically compile, build and display the results in one of the screens. An example of a sharable link from Godbolt is here.