fsharp-dotnet, 137 bytes

Result

AC

Duration

7201ms

Code [DL]

let rec f x=let c=stdin.Read()in let x=(match c with-1->1/0|84->0|75->x-50|_->x+1)%51 in stdout.Write(if x<1 then 'x'else char c);f x
f 0

stdin

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stdout

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stderr

The template "Console Application" was created successfully.

Processing post-creation actions...
Running 'dotnet restore' on /tmp/Proj/Proj.fsproj...
  Restoring packages for /tmp/Proj/Proj.fsproj...
  Generating MSBuild file /tmp/Proj/obj/Proj.fsproj.nuget.g.props.
  Generating MSBuild file /tmp/Proj/obj/Proj.fsproj.nuget.g.targets.
  Restore completed in 210.66 ms for /tmp/Proj/Proj.fsproj.

Restore succeeded.


Unhandled Exception: System.DivideByZeroException: Attempted to divide by zero.
   at Program.f[a](Int32 x) in /tmp/Proj/Program.fs:line 1
   at <StartupCode$Proj>.$Program.main@() in /tmp/Proj/Program.fs:line 2

strace