JSLint says "missing radix parameter"

It always a good practice to pass radix with parseInt -

parseInt(string, radix)

For decimal -

parseInt(id.substring(id.length - 1), 10)

If the radix parameter is omitted, JavaScript assumes the following:

• If the string begins with "0x", the radix is 16 (hexadecimal)
• If the string begins with "0", the radix is 8 (octal). This feature is deprecated
• If the string begins with any other value, the radix is 10 (decimal)

(Reference)

To avoid this warning, instead of using:

parseInt("999", 10);

You may replace it by:

Number("999");

^{Note that parseInt and Number have different behaviors, but in some cases, one can replace the other.}