## trimatoi
### Instructions
- Write a function that transforms a number within a `string` in a number represented as an `int` .
- For this exercise the handling of the signs + or - **has** to be taken into account. If one of the signs is encountered before any number it should determine the sign of the returned `int` .
- This function will **only** have to return the `int` . In case of invalid input, the function should return `0` .
- Note: There will never be more than one sign by string in the tests.
### Expected function
```go
func TrimAtoi(s string) int {
}
```
### Usage
Here is a possible program to test your function :
```go
package main
import (
"fmt"
piscine ".."
)
func main() {
s := "12345"
s2 := "str123ing45"
s3 := "012 345"
s4 := "Hello World!"
s5 := "sd+x1fa2W3s4"
s6 := "sd-x1fa2W3s4"
s7 := "sdx1-fa2W3s4"
n := piscine.TrimAtoi(s)
n2 := piscine.TrimAtoi(s2)
n3 := piscine.TrimAtoi(s3)
n4 := piscine.TrimAtoi(s4)
n5 := piscine.TrimAtoi(s5)
n6 := piscine.TrimAtoi(s6)
n7 := piscine.TrimAtoi(s7)
fmt.Println(n)
fmt.Println(n2)
fmt.Println(n3)
fmt.Println(n4)
fmt.Println(n5)
fmt.Println(n6)
fmt.Println(n7)
}
```
And its output :
```console
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
12345
12345
12345
0
1234
-1234
1234
student@ubuntu:~/[[ROOT]]/test$
```
