# 2.9.jl
# 2024-09-04
# $Id: 2.9.jl 1.1 2024/10/26 22:36:07 s Exp $

# input
r = 0.05
pv = 20e3
n1 = 20
n2 = 5
i1 = range(1, n1 + 1)
i2 = range(1, n2 + 1)

# calculating
sum_df1 = sum(map(x -> 1 / (1 + r) ^ x, i1))
sum_df2 = sum(map(x -> 1 / (1 + r) ^ x, i2))
x = pv / sum_df1
v = x * sum_df2

# output
println("2.9.jl")
println("r= ",r)
println("pv(\$)= ", pv)
println("n1= ", n1)
println("n2= ", n2)
println("i1= ", i1)
println("i2= ", i2)
println("total of discount factors= ",    round(sum_df1, digits=1))
println("each year's cost(\$)= ",         round(x, digits=1))
println("present value of the roof(\$)= ",round(v, digits=1))
# end