sum := 0.0
k := 0

iterations := 100

while k < iterations {
	k_f := float(k)
	sum = sum + 1.0 / pow(16.0, k_f) *
		(4.0 / (8.0 * k_f + 1.0) -
		 2.0 / (8.0 * k_f + 4.0) -
		 1.0 / (8.0 * k_f + 5.0) -
		 1.0 / (8.0 * k_f + 6.0))
	k = k + 1
}

put("π ≈ ")
putln(sum)