public/subjects/unzipstring/README.md

Unzipstring

Instructions

Write a function called Unzipstring that takes a string that will be a kind of code, and your function will have to decrypt it and return a new string with the output. It works as follows: The string will be formed by a number followed by a letter, and the purpose is to print this letter the number of times that is requested by the number that precedes it.

"3w" ==> www
"2m3e" ==> mmee

• The number before the letter must be between 0 and 9.
• The letter after each number must be between a and z or A and Z.
• You cannot have two numbers or two letters in a row.
• If the input string does not respect the format, return Invalid Input.

Expected Function

func Unzipstring(s string) string {
}

Usage

Here is a possible program to test your function:

package main

import "fmt"

func main() {
    fmt.Println(Unzipstring("2f"))
    fmt.Println(Unzipstring("2O5u2H0e"))
    fmt.Println(Unzipstring("3p6i1W"))
    fmt.Println(Unzipstring("6H8a"))
    fmt.Println(Unzipstring("2p4;7g"))
    fmt.Println(Unzipstring("2a 6p8f"))
    fmt.Println(Unzipstring("2t4dD"))
    fmt.Println(Unzipstring("82t4D"))
    fmt.Println(Unzipstring(""))
}

And its output :

$ go run .
$ff
$OOuuuuuHH
$pppiiiiiiW
$HHHHHHaaaaaaaa
$Invalid Input
$Invalid Input
$Invalid Input
$Invalid Input
$Invalid Input