What is the shortest LOOP program that outputs 2016? Use a minor restriction of the LOOP language described under Wikipedia's "LOOP (Programming Language)". The restriction is to eliminate constants. So, the language contains increment: $x_i++$, 
decrement: $x_i--$, assignment: $x_i := x_j$, sequencing and loop.
The output of the program is the final value of $x_0$, and the length of a program is the
total count of increment/decrement/assignment/loop. For example, the following program has a length of 8 and outputs 34. (I use x and y instead of $x_0$ and $x_1$.)
x++
y++
y++
loop y
  loop y
    y++
    loop y
      x++

Notes:


*

*I have added the recreational-mathematics tag, as this question is similar to "Small Representations of 2016".

*This question is mainly for fun, but hopefully more challenging/interesting than the usual questions asking to use certain digits. 

*As explained in Wikipedia all variables are implicitly initialized to 0.

*Programmers should also find this challenging. 

*It is not an official contest, so I am not cheating!
 A: Totally serious answer, tongue nowhere near interior of cheek: This is trivial.
Presumably another condition is that all variables shall be initialized to $0$, since otherwise
x_0:=x_1

would work if $x_1$ is initialized properly.
The restriction that $c$ is $0$ or $1$ means that there are only finitely many programs of length no larger than $n$ using no more than $v$ variables. So it's trivial to write a Python script to calculate $L(n)$, the length of the shortest program that outputs $n$: There is such a program of length $n$. A program of length no larger than $n$ cannot assign values to more than $n$ variables. So enumerate all the programs of length less than or equal to $n$ using only the variables $x_0,\dots,x_n$, execute each one to see whether it outputs $n$ and record the length if it does.
Probably we won't get an answer for $L(2016)$ before the year 2017. Next question: Does there exist $n$ such that we can calculate $L(n)$ by this method and have it return before year $n$?
