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authorDenys Vlasenko2017-04-13 10:51:13 +0200
committerDenys Vlasenko2017-04-13 10:51:13 +0200
commitc054822027a4a6895bc95979c6c10ff5763c7c7e (patch)
tree20fb208d1e2bab309b76b007551b344e6ed34133
parent6c149f4d9afaed9edb75c88b784ad900c1f40700 (diff)
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factor: tweak comments
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--coreutils/factor.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/coreutils/factor.c b/coreutils/factor.c
index 66d6a7c..7adc238 100644
--- a/coreutils/factor.c
+++ b/coreutils/factor.c
@@ -58,7 +58,7 @@ static NOINLINE void factorize(wide_t N)
// unsigned count3;
// unsigned count5;
// unsigned count7;
- // ^^^^^^^^^^^^^^^ commented-out simple siving code (easier to grasp).
+ // ^^^^^^^^^^^^^^^ commented-out simple sieving code (easier to grasp).
// Faster sieving, using one word for potentially up to 6 counters:
// count upwards in each mask, counter "triggers" when it sets its mask to "100[0]..."
// 10987654321098765432109876543210 - bits 31-0 in 32-bit word
@@ -94,6 +94,8 @@ static NOINLINE void factorize(wide_t N)
* 18446744073709551601 = 53 348051774975651917
* the last factor requires testing up to
* 589959129 - about 100 million iterations.
+ * The slowest case (largest prime) for N < 2^64 is
+ * factor 18446744073709551557 (0xffffffffffffffc5).
*/
max_factor = isqrt_odd(N);
// count3 = 3;