Powershell Read-Host Not adding or multiplying correctly?

Question

What exactly am I doing wrong here, it seems to be subtracting just fine but adding and multiplying seems to not work at all.

How do I get it to do the calculations correct and allow the if statement to also work as it seems to always run even if the numbers are incorrect size.

$a = Read-Host "What is your name?"
$b = Read-Host "Enter a 2 digit number" 
$c = Read-Host "Enter a 3 digit number" 




if (($b -ge 10) -and ($b -le 99) -and ($c -ge 100) -and ($c -le 999)){


$d = $b + $c
$e = $b * $c
$g = $b - $c

$d
$e
$g


Write-host "Here you go $a"

}
else {

write-host "Enter the numbers correctly"

}

Here the results I get

Answer 1

Read-Host always outputs a string .

In order to treat the output as a number , you must explicitly convert it to one :

$a = Read-Host "What is your name?"
[int] $b = Read-Host "Enter a 2 digit number" 
[int] $c = Read-Host "Enter a 3 digit number" 

The above type-constrains variables $b and $c to integer values (by placing the [int] cast to the left of the target variable in the assignment), which automatically converts Read-Host 's [string] output to [int] .

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As for what you tried :

Except for - , all the operators used in your code have string-specific overloads (meaning) ; note that it is sufficient for the LHS to be of type [string] to trigger this behavior. ^[1]

• -lt / -ge perform lexical comparison with strings; eg, '10' -gt '2' yields $false , because, in lexical sorting, string '10' comes before string '2' .

• -and / -or treat empty strings as $false , and any nonempty string as $true ; eg,
  '0' -and '0' is $true , because '0' is a nonempty string.

• + performs string concatenation ; eg, '1' + '0' is '10' .

• * performs string replication ; eg, '1' * 3 is '111' - the LHS is repeated as many times as specified by the number on the RHS; note that '1' * '3' works the same, because the RHS is coerced to an [int] in this case.

• - is the only exception : it always performs a numeric operation, if possible; eg, '10' - '2' yields 8 , because both operands were implicitly converted to [int] s.

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^{[1] Typically, it is the LHS of an operation that determines its data type, causing the RHS to be coerced to a matching type, if necessary.}