4. Significantly reduce the risk that your smart contract will lose its balance to an [avoidable exploit](https://www.wired.com/2016/06/50-million-hack-just-showed-dao-human/).
Let's define some LIGO contract in the three flavours above. Do
not worry if it is a little confusing at first; we will explain all
the syntax in the upcoming sections of the documentation.
<!--DOCUSAURUS_CODE_TABS-->
<!--PascaLIGO-->
```pascaligo group=a
type storage is int
type parameter is
Increment of int
| Decrement of int
| Reset
type return is list (operation) * storage
function main (const action : parameter; const store : storage) : return is
((nil : list (operation)),
case action of
Increment (n) -> store + n
| Decrement (n) -> store - n
| Reset -> 0
end)
```
<!--CameLIGO-->
```cameligo group=a
type storage = int
type parameter =
Increment of int
| Decrement of int
| Reset
type return = operation list * storage
let main (action, store : parameter * storage) : return =
([] : operation list),
(match action with
Increment n -> store + n
| Decrement n -> store - n
| Reset -> 0)
```
<!--ReasonLIGO-->
```reasonligo group=a
type storage = int;
type parameter =
Increment (int)
| Decrement (int)
| Reset;
type return = (list (operation), storage);
let main = ((action, store): (parameter, storage)) : return => {
(([] : list (operation)),
(switch (action) {
| Increment (n) => store + n
| Decrement (n) => store - n
| Reset => 0}));
};
```
<!--END_DOCUSAURUS_CODE_TABS-->
This LIGO contract accepts the following LIGO expressions:
`Increment(n)`, `Decrement(n)` and `Reset`. Those serve as
`entrypoint` identification.
---
## Runnable code snippets & exercises
Some of the sections in this documentation will include runnable code snippets and exercises. Sources for those are available at
the [LIGO Gitlab repository](https://gitlab.com/ligolang/ligo).
### Snippets
For example **code snippets** for the *Types* subsection of this doc, can be found here:
`gitlab-pages/docs/language-basics/src/types/**`
### Exercises
Solutions to exercises can be found e.g. here: `gitlab-pages/docs/language-basics/exercises/types/**/solutions/**`
### Running snippets / exercise solutions
In certain cases it makes sense to be able to run/evaluate the given snippet or a solution, usually there'll be an example command which you can use, such as:
```shell
ligo evaluate-value -s pascaligo gitlab-pages/docs/language-basics/src/variables-and-constants/const.ligo age
