Return First and Last Parameter

Write two functions:

1. firstArg() should return the first parameter passed in.
2. lastArg() should return the last parameter passed in.

Examples

firstArg(1, 2, 3) ➞ 1

lastArg(1, 2, 3) ➞ 3

firstArg(8) ➞ 8

lastArg(8) ➞ 8

Notes

• Return undefined if the function takes no parameters.
• If the function only takes in one parameter, the firstArg and lastArg functions should return the same value.
• JavaScript has an arguments object which keeps track of the parameters being passed in.