# [C# (Visual C# Interactive Compiler)], 73 bytes <!-- language-all: lang-cs --> a=>b=>{int i=0;return a.Select(x=>x>45&&b.Contains(++i)?(char)(x^40):x);} [Try it online!][TIO-jyk5jafm] [C# (Visual C# Interactive Compiler)]: http://www.mono-project.com/docs/about-mono/releases/5.0.0/#csc [TIO-jyk5jafm]: https://tio.run/##dY2xasMwFEV3f4XIEPSIHNzWWSJLCZQWCtk6dCgxSKrSPkgVkJ5Tg8m3u3YypFDC5S6Xw7ku5S5h/9wEV708hebbR2P3vnJfJmpxmTeYqMJAWvwjtN6p3ihtle4GgqEqZPTUxMDM/NXvvSPeKt3qcjGd2vnjIZDBkPhshrDiowJ4W5cFLFuQp15mxwN@MPKJ@PXWCJYoYvhkFrq3iOQ3GDy/bKPTGeI7boEbAJBXYlBmZ1fwP@/b7l48iMVJrCd5nR@HZOfWQyYg/4KFuBMjXN7G@18 "C# (Visual C# Interactive Compiler) – Try It Online"