In a park with a perimeter of 18 kilometers (km), Soyun and Jia started off at the same time from the same place, but in opposite directions, and met on the way. It is said that Soyun ran at 5 kilometers (km) per hour and Jia ran at 4 kilometers (km) per hour. How far did Soyun run?
18 5 4 [OP_ADD] [OP_DIV] 5 [OP_MUL]
var_a = 18
var_b = 5
var_c = 4
var_d = var_b + var_c
var_e = var_a / var_d
var_f = 5
var_g = var_e * var_f
print(int(var_g))