I paid 1,000 won and bought several pencils for 210 won and a glue for 270 won. How many pencils did you buy in total when you received 100 won in change?
1000 100 [OP_SUB] 270 1 [OP_MUL] [OP_SUB] 210 [OP_DIV]
var_a = 1000
var_b = 100
var_c = var_a - var_b
var_d = 270
var_e = 1
var_f = var_d * var_e
var_g = var_c - var_f
var_h = 210
var_i = var_g / var_h
print(int(var_i))