[R] Adding elements in an array where I have missing data.

[John Kane]

This is a simple question but I cannot seem to find
the answer.
I have two vectors but with missing data and I want to
add them together with
the NA's being ignored.

Clearly I need to get the NA ignored.  na.action?

I have done some searching and cannot get na.action to
help.
This must be a common enough issue that the answer is
staring me in the face
but I just don't see it.

Simple example
a <- c(2, NA, 3)
b <- c(3,4, 5)

What I want is
c <- a + b where
c  is ( 5 , 4 ,8)

However I get
c is (5,NA, 8)

What am I missing?  Or do I somehow need to recode the
NA's as missing?  

Thanks