iRule to redirect based on availability

I'm looking to only redirect if the request contains /C, other requests should always go to the other pools.

e.g.

when RULE_INIT {
   pool names
  set static::poola "a"
  set static::poolb "b"
  set static::poolc "c"
  set static::pooldefault "default"
}
when HTTP_REQUEST {
  switch -glob [string tolower [HTTP::uri]] {
    "/a/*" { 
      pool $static::poola
    }
    "/b/*" { 
      pool $static::poolb
    }
    "/c/*" { 
      if { [active_members $static:poolc] > 0 } {
        pool $static::poolc
      } else {
        pool $static::pooldefault
      }
    }
    default { 
       do something
    }
  }
}