Integer userNum is read from input. Write a while loop that iterates until userNum is negative. At each iteration:

Update integer finalNum as follows:

If userNum is even, add userNum to finalNum.

Otherwise, subtract userNum from finalNum.

Then, read an integer from input into variable userNum.

End each output with a newline.

Ex: If the input is 6 4 3 -2, then the output is:

Final number is 7

Note: x % 2 == 0 returns true if x is even.