Letter Coding for HAPPINESS

The pattern alternates $+1, -1, +1, -1, \dots$ on consecutive letters: $H (+1) \rightarrow I$ $A (-1) \rightarrow Z$ $P (+1) \rightarrow Q$ $P (-1) \rightarrow O$ $I (+1) \rightarrow J$ $N (-1) \rightarrow M$ $E (+1) \rightarrow F$ $S (-1) \rightarrow R$ $S (+1) \rightarrow T$ Combining these yields IZQOJMFRT.