In a herd of 93 goats, there are black and white goats. There are 66 black goats, and the rest are white goats. If 21 new black goats came in and as many black goats died as white goats, how many black goats will there be?
66 93 66 [OP_SUB] [OP_SUB] 21 [OP_ADD]
var_a = 66
var_b = 93
var_c = 66
var_d = var_b - var_c
var_e = var_a - var_d
var_f = 21
var_g = var_e + var_f
print(int(var_g))