What simple C/C++ or java program can be ported to C#?

Question

Programming

What simple C/C++ or java (or other open source language) program can be ported to C#? It is desirable with gui, but it is possible and console.
PS: I want to test my skills in C#.

Answer 1

Any simple program can be ported to another language if it has Turing completeness.

Answer 2

Why port? Write a decentralized P2P app, develop a graphics engine for 3D games, write your own web server with blackjack and whores, build the most secure messenger, anything from scratch.
Set your source material not to open source, but to an idea.
If you want to learn a language, set the bar higher. So, without knowing any language, I take and write a complex tool purely for my own use, and it turns out that I study the language in parallel.

Answer 3

Apache POI library. You can not all, but only to support Xls and Doc formats. Nothing complicated, serialization and deserialization of binary files, there is nothing else in it. And check your skills properly, in particular, the skill to rewrite at least 1/10 of the entire Microsoft Office alone.