# 0080: Non-negative integer number expected

The compiler expects a number greater than or equal to zero but finds something different.

For example, the error could be thrown if a negative number is used for the array [element index](https://docs.sannybuilder.com/language/data-types/arrays#accessing-array-elements-after-declaration) or as the second parameter to the `Alloc` [command](https://docs.sannybuilder.com/language/instructions/built-in-commands#alloc).

**Possible solutions:** use a number greater than or equal to zero:

```
$var[-1] = 0 // error
$var[1] = 0 // OK
```