  The charge is an intricate statistic on words, due to Lascoux and
Schutzenberger, which gives positive combinatorial formulas for Lusztig's
q-analogue of weight multiplicities and the energy function on affine crystals,
both of type A. As these concepts are defined for all Lie types, it has been a
long-standing problem to express them based on a generalization of charge. I
present a method for addressing this problem in classical Lie types, based on
the recent Ram-Yip formula for Macdonald polynomials and the quantum Bruhat
order on the corresponding Weyl group. The details of the method are carried
out in type A (where we recover the classical charge) and type C (where we
define a new statistic).
