Out of 15 chickens, there are only 3 hens. If there are 4 chicks fewer than the number of roosters, how many chicks are there?
15 3 [OP_SUB] 4 [OP_SUB]
var_a = 15
var_b = 3
var_c = var_a - var_b
var_d = 4
var_e = var_c - var_d
print(int(var_e))