if (a && b || c && d || e) // wtf? Don't make me guess what you intended!
if ((a && b) || (c && d) || e) // clear
if (a && (b || c) && (d || e)) // as clear, but a very different condition
if (a && (b || (c && (d || e)))) // a different condition
if ((((a && b) || c) && d) || e) // another different condition

##</code><code>##

if ((((((((a && b))) || (((c)))))))) // make extra-sure that parentheses have precedence ;-)

##</code><code>##

if (
    ((a == A_MAGIC_1) || (a == A_MAGIC_2))
    &&
    ((b == B_MAGIC_1) || (b == B_MAGIC_2))
    &&
    (
        (c == C_MAGIC_1) 
        || 
        ((c == C_MAGIC_2) && (a == A_MAGIC_2) && (b == B_MAGIC_2))
    )
)