using Base.Threads

println("Active Julia threads: ", nthreads())

# A CPU-heavy helper function
function compute_work(id, iterations)
    println("  [Start] Task $id on Thread #", threadid())
    
    total = 0.0
    for i in 1:iterations
        total += sin(i) * cos(i)
    end
    
    println("  [Done]  Task $id on Thread #", threadid())
    return total
end

# ====================================================================
# 1. Basic @spawn and fetch
# ====================================================================
println("\n--- 1. Single Task Spawning ---")

# Threads.@spawn creates a Task and schedules it onto an available worker thread
task1 = Threads.@spawn compute_work("A", 10_000_000)
println(typeof(task1))