Update input.md

Fixed broken link.
hof: Removed unnecessary "if" in is_odd() definition.
hof: remove extern

Crate ‘num’ is not required to compile but breaks ‘Run’ button on
website
No more Vec::get() method in rust
Fixed mut_iter() to iter_mut()
Fixed redundancies in struct patterns
Fix the language in Lifetime's "grok" expression

The expression did not quite work in English. The following sentence was also missing a full-stop.
Check the description

make all:
* Changed all `fail!()`s to `panic!()`s
* Changed current working directory to unwrap the result

make clean: Changed `rm -rf {bin,stage}` (which doesn't work) to
    `rm -rf bin stage`
Fixed everything else

makefile:
* Changed lints to be correct
  * unused-variable -> unused-variables
  * dead-assignment -> unused-assignments

rust files:
* Changed fail!() calls to panic!() calls
* Changed some syntax so that slices are correct
  * i.e. in array.rs (analyze_slice(xs) -> analyze_slice(&xs))
* Namespaced enums
* Renamed `Node` to `List` in enum.rs
  * Renamed List::append() to List::prepend(), which is the actual
    operation that is taking place
* Renamed fail/fail.rs to panic/panic.rs
  * And everything that comes with that
* Changed any `{:t}`s to `{:b}`s
* `use`d std::num::Float in places that needed it
* In fmt/show.rs, changed {:.3f} to {:.3}
* Changed hash table .find() to .get()
  * Took out the parens in a string .get(), so that
    `h.get(&("string"))` becomes `h.get(&"string")`
* Completely removed smallintmap
* In json/decodable/decodable.rs, changed {:.2f} to {:.2}
* In src/file.rs, changed a comment to be under 79 characters long
Say the explicit build commands to generate the docs in README.md
Fix dead_code warnings
fixed comment for example one

I believe Rust now infers the lifetime for the case described in the first example.
calling first example in main function
fixed Mul trait implementation for Vec2<T>

* added missing trait and struct name for Mul trait implementation
* use of current function name (mul instead of dot)
Fix build instructions
add example of initializing an array without literal

There was no example on how to initialize an array except for using a literal. For large arrays, initialization using a literal is not really an option.
Remove bin file