The straight line drawn by the Yoojeong is 3 millimeters (mm) shorter than 31 centimeters (cm). Write the length of the straight line drawn by Yoojeong in millimeters (mm).
31 10 [OP_MUL] 3 [OP_SUB]
var_a = 31
var_b = 10
var_c = var_a * var_b
var_d = 3
var_e = var_c - var_d
print(int(var_e))