<?php
function gdr_encode($val) {
// all characters that json encode without escaping
$chrs = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789 !#$%&\'()*+,-.:;<=>?@[]^_`{|}~';
$base = strlen($chrs);
$str = '';
while ($val > 0) {
$str = $chrs[$val % $base] . $str;
$val = (int)($val / $base);
}
return $str;
}
function gdr_decode($str) {
// all characters that json encode without escaping
$chrs = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789 !#$%&\'()*+,-.:;<=>?@[]^_`{|}~';
$base = strlen($chrs);
$map = array();
for ($i=0; $i<$base; $i++) {
$map[$chrs[$i]] = $i;
}
$val = 0;
for ($i=0; $i<strlen($str); $i++) {
$val *= $base;
$val += (int)$map[$str[$i]];
}
return $val;
}
function duration($val) {
if ($val < 24) {
return sprintf('%d', $val).'h';
}
if ($val < 24*10) {
return sprintf('%1.1f', $val/24).'d';
}
if ($val < 168*10) {
return sprintf('%1.1f', $val/168).'w';
}
//if ($val < 730*10) {
// return sprintf('%1.1f', $val/730).'m';
//}
return sprintf('%1.1f', $val/8760).'y';
}
function cmp($val) {
return strlen(gdr_encode($val))+2-strlen($val);
}
function insert(&$vals, $n) {
$min = intval('1'.str_repeat('0', $n-1));
$max = intval(str_repeat('9', $n));
$vals[] = $min;
$vals[] = $max;
$cmp_min = cmp($min);
$cmp_max = cmp($max);
if ($cmp_min === $cmp_max) {
return;
}
if ($cmp_min+1 !== $cmp_max) {
echo "BAD SEARCH ASSUMPTION: [$min => $cmp_min, $max => $cmp_max]\n";
}
while ($min <= $max) {
$mid = (int)(($min+$max)/2);
$cmp_mid = cmp($mid);
echo "trace: [$min => $cmp_min, $mid => $cmp_mid, $max=>$cmp_max]\n";
if ($cmp_min === $cmp_mid && $cmp_mid !== cmp($mid+1)) {
$vals[] = $mid;
$vals[] = $mid+1;
return;
}
if ($min === $max) {
return;
}
if ($cmp_min < $cmp_mid) {
$max = $mid-1;
} else {
$min = $mid+1;
}
}
}
$vals = array(0);
for ($i=1; $i<8; $i++) {
insert($vals, $i);
}
$vals = array_unique($vals);
sort($vals);
echo sprintf("%7s %7s %7s %4s\n", 'num', 'str', 'time', 'cmp');
foreach ($vals as $val) {
$enc = gdr_encode($val);
$dec = gdr_decode($enc);
if ($dec !== $val) {
echo "ERROR: $val => $enc => $dec\n";
} else {
echo sprintf("%7d %7s %7s %4d\n", $dec, "\"$enc\"", duration($val), cmp($val));
}
}
- Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
- trace: [10 => 1, 54 => 1, 99=>2]
trace: [55 => 1, 77 => 1, 99=>2]
trace: [78 => 1, 88 => 1, 99=>2]
trace: [89 => 1, 94 => 2, 99=>2]
trace: [89 => 1, 91 => 1, 93=>2]
trace: [1000 => 0, 5499 => 0, 9999=>1]
trace: [5500 => 0, 7749 => 0, 9999=>1]
trace: [7750 => 0, 8874 => 1, 9999=>1]
trace: [7750 => 0, 8311 => 0, 8873=>1]
trace: [8312 => 0, 8592 => 1, 8873=>1]
trace: [8312 => 0, 8451 => 0, 8591=>1]
trace: [8452 => 0, 8521 => 1, 8591=>1]
trace: [8452 => 0, 8486 => 1, 8520=>1]
trace: [8452 => 0, 8468 => 1, 8485=>1]
trace: [8452 => 0, 8459 => 0, 8467=>1]
trace: [8460 => 0, 8463 => 0, 8467=>1]
trace: [100000 => -1, 549999 => -1, 999999=>0]
trace: [550000 => -1, 774999 => -1, 999999=>0]
trace: [775000 => -1, 887499 => 0, 999999=>0]
trace: [775000 => -1, 831249 => 0, 887498=>0]
trace: [775000 => -1, 803124 => 0, 831248=>0]
trace: [775000 => -1, 789061 => 0, 803123=>0]
trace: [775000 => -1, 782030 => 0, 789060=>0]
trace: [775000 => -1, 778514 => -1, 782029=>0]
trace: [778515 => -1, 780272 => 0, 782029=>0]
trace: [778515 => -1, 779393 => 0, 780271=>0]
trace: [778515 => -1, 778953 => 0, 779392=>0]
trace: [778515 => -1, 778733 => 0, 778952=>0]
trace: [778515 => -1, 778623 => -1, 778732=>0]
trace: [778624 => -1, 778678 => -1, 778732=>0]
trace: [778679 => -1, 778705 => 0, 778732=>0]
trace: [778679 => -1, 778691 => 0, 778704=>0]
trace: [778679 => -1, 778684 => -1, 778690=>0]
trace: [778685 => -1, 778687 => -1, 778690=>0]
num str time cmp
0 "" 0h 1
1 "B" 1h 2
9 "J" 9h 2
10 "K" 10h 1
91 "~" 3.8d 1
92 "BA" 3.8d 2
99 "BH" 4.1d 2
100 "BI" 4.2d 1
999 "K=" 5.9w 1
1000 "K>" 6.0w 0
8463 "~~" 1.0y 0
8464 "BAA" 1.0y 1
9999 "BQ!" 1.1y 1
10000 "BQ#" 1.1y 0
99999 "L-`" 11.4y 0
100000 "L-{" 11.4y -1
778687 "~~~" 88.9y -1
778688 "BAAA" 88.9y 0
999999 "BaNz" 114.2y 0
1000000 "BaN0" 114.2y -1
9999999 "M;r7" 1141.6y -1
preferences:
229.11 ms | 414 KiB | 325 Q