From 12dc4fbf188673a9048fc98eff371a83e9c367dc Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Mon, 10 Apr 2017 00:41:11 +0200 Subject: factor: fix comments Signed-off-by: Denys Vlasenko --- coreutils/factor.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/coreutils/factor.c b/coreutils/factor.c index 8ca3de7..4e521db 100644 --- a/coreutils/factor.c +++ b/coreutils/factor.c @@ -54,7 +54,7 @@ static inline half_t isqrt(wide_t N) // if (N == 0) // return 0; - /* First approximation x > sqrt(N) - half as many bits: + /* First approximation of x+1 > sqrt(N) - all-ones, half as many bits: * 1xxxxx -> 111 (six bits to three) * 01xxxx -> 111 * 001xxx -> 011 @@ -125,7 +125,7 @@ static NOINLINE void factorize(wide_t N) if (factor >= max_factor) break; factor += 2; - /* Rudimentary wheel sieving: skip multiples of 3: + /* Rudimentary wheel sieving: skip multiples of 3, 5 and 7: * Every third odd number is divisible by three and thus isn't a prime: * 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47... * ^ ^ ^ ^ ^ ^ ^ _ ^ ^ _ ^ ^ ^ ^ -- cgit v1.1