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2020-12-23factor: fix commentDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-12-22factor: detect squaresDenys Vlasenko
If we have a square, the speedup can be extremely large (in best case example below, it's ~40000 times faster): $ time ./busybox_old factor 18446743988964486098 18446743988964486098: 2 3037000493 3037000493 real 0m4.246s $ time ./busybox factor 18446743988964486098 18446743988964486098: 2 3037000493 3037000493 real 0m0.000s function old new delta isqrt_odd - 57 +57 print_w - 36 +36 factorize 218 236 +18 print_h - 7 +7 factorize_numstr 65 72 +7 ------------------------------------------------------------------------------ (add/remove: 3/0 grow/shrink: 2/0 up/down: 125/0) Total: 125 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-12-21factor: fix typo in undefDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-12-21factor: code shrinkDenys Vlasenko
function old new delta factor_main 176 171 -5 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-12-20factor: 30% faster trial division (better sieve)Denys Vlasenko
function old new delta packed_wheel - 192 +192 factor_main 108 176 +68 factorize 284 218 -66 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 1/1 up/down: 260/-66) Total: 194 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-12-28config: update size informationDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-21config: deindent all help textsDenys Vlasenko
Those two spaces after tab have no effect, and always a nuisance when editing. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-18Update menuconfig items with approximate applet sizesDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-17factor: fix stray semicolonDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-14factor: support "no-argvs" usageDenys Vlasenko
function old new delta factorize_numstr - 72 +72 packed_usage 31562 31566 +4 factor_main 109 101 -8 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 1/1 up/down: 76/-8) Total: 68 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-13factor: improve comments for sieving logic... also fix a typoDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-13factor: improve comments for sieving logicDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-13factor: tweak commentsDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-11factor: remove debug codeDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-11libbb: move isqrt from factor, use it in diff tooDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-11factor: much faster, and very slightly larger isqrt()Denys Vlasenko
function old new delta isqrt_odd 70 88 +18 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: don't be too clever in isqrt - be small insteadDenys Vlasenko
function old new delta isqrt_odd 111 70 -41 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: add code to test isqrt() correctnessDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: 25% faster sievingDenys Vlasenko
function old new delta factorize 287 260 -27 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: better comments, slightl more clever conversion even->oddDenys Vlasenko
function old new delta isqrt_odd 114 111 -3 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: fix HALF_FMT usageDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: fix commentsDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: a bit more simple isqrtDenys Vlasenko
function old new delta isqrt_odd 87 80 -7 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-10factor: simpler isqrtDenys Vlasenko
function old new delta isqrt_odd 102 87 -15 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-09factor: factor2 variable is unused now, drop itDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-09factor: expand commentsDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-09factor: 30% faster code (estimate max possible factor just once)Denys Vlasenko
function old new delta factorize - 161 +161 isqrt_odd - 102 +102 factor_main 281 110 -171 ------------------------------------------------------------------------------ (add/remove: 2/0 grow/shrink: 0/1 up/down: 263/-171) Total: 92 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-04-09factor: new appletDenys Vlasenko
thus far only able to factor up to ULLONG_MAX function old new delta factor_main - 378 +378 packed_usage 31427 31502 +75 applet_names 2590 2597 +7 applet_main 1500 1504 +4 ------------------------------------------------------------------------------ (add/remove: 2/0 grow/shrink: 3/0 up/down: 464/0) Total: 464 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
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