With 25,000 won, you bought two roses for 3,000 won and several lilies for 2,800 won. To get 2,200 won in change, find how many lilies you need to buy.
25000 2200 [OP_SUB] 3000 2 [OP_MUL] [OP_SUB] 2800 [OP_DIV]
var_a = 25000
var_b = 2200
var_c = var_a - var_b
var_d = 3000
var_e = 2
var_f = var_d * var_e
var_g = var_c - var_f
var_h = 2800
var_i = var_g / var_h
print(int(var_i))