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## box_it
### Instructions
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Create the following **functions**:
- `transform_and_save_on_heap`: which accepts a string of numbers separated by spaces. If a number has a `'k'` as a suffix it should be multiplied by 1000. The function transforms those numbers into a vector of `u32`, and saves them in the heap using `Box`.
- `take_value_ownership`: which accepts the return value from `transform_and_save_on_heap`, unboxes the value, and returns it.
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### Expected Functions
```rust
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pub fn transform_and_save_on_heap(s: String) -> Box<Vec<u32>> {
}
pub fn take_value_ownership(a: Box<Vec<u32>>) -> Vec<u32> {
}
```
### Usage
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Here is a program to test your functions
```rust
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use box_it::*;
fn main() {
let new_str = String::from("5.5k 8.9k 32");
// creating a variable and we save it in the Heap
let a_h = transform_and_save_on_heap(new_str);
println!("Box value : {:?}", &a_h);
println!("size occupied in the stack : {:?} bytes", (std::mem::size_of_val(&a_h)));
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let a_b_v = take_value_ownership(a_h);
println!("value : {:?}", &a_b_v);
println!("size occupied in the stack : {:?} bytes", (std::mem::size_of_val(&a_b_v)));
// whenever the box, in this case "a_h", goes out of scope it will be deallocated, freed
}
```
And its output:
```console
$ cargo run
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Box value : [5500, 8900, 32]
size occupied in the stack : 8 bytes
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value : [5500, 8900, 32]
size occupied in the stack : 24 bytes
$
```
### Notions
- [smart pointers](https://doc.rust-lang.org/book/ch15-00-smart-pointers.html)
- [using box](https://doc.rust-lang.org/book/ch15-01-box.html)