Find the sum of the lengths of the edges of a regular tetrahedron with a side length of 3 centimeters (cm) plus 3.
3 6 3 [OP_MUL] [OP_ADD]
var_a = 3
var_b = 6
var_c = 3
var_d = var_b * var_c
var_e = var_a + var_d
print(int(var_e))