There is a square piece of land with a side length of 4 kilometers (km). A rhombus-shaped park was created by connecting the points that divided the four sides of the land into two equally. Find the area of the park.
4 4 [OP_MUL] 2 [OP_DIV]
var_a = 4
var_b = 4
var_c = var_a * var_b
var_d = 2
var_e = var_c / var_d
print(int(var_e))