diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c5295b..1a7287c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -27,3 +27,10 @@
 3. 新增：每日宜忌、时辰宜忌。
 4. 新增：支持方法扩展。
 5. 修复：农历日获取时辰列表遇闰月报错的问题。
+
+## [1.1.1] - 2024-07-30
+1. 新增：时辰获取黄道黑道十二神。
+2. 新增：五行和方位互转。
+3. 新增：天干五合、地支六合、地支六害。
+4. 修复：获取当年第几周报错的问题。
+5. 优化：性能。
diff --git a/src/culture/Direction.php b/src/culture/Direction.php
index 3432151..cb4edc7 100644
--- a/src/culture/Direction.php
+++ b/src/culture/Direction.php
@@ -50,4 +50,14 @@ function getLand(): Land
     {
         return Land::fromIndex($this->index);
     }
+
+    /**
+     * 五行
+     *
+     * @return Element 五行
+     */
+    function getElement(): Element
+    {
+        return Element::fromIndex([4, 2, 0, 0, 2, 3, 3, 2, 1][$this->index]);
+    }
 }
diff --git a/src/culture/Element.php b/src/culture/Element.php
index 761ef05..c1e82b6 100644
--- a/src/culture/Element.php
+++ b/src/culture/Element.php
@@ -77,4 +77,13 @@ function getRestrained(): static
     {
         return $this->next(-2);
     }
+
+    /**
+     * 方位
+     * @return Direction 方位
+     */
+    function getDirection(): Direction
+    {
+        return Direction::fromIndex([2, 8, 4, 6, 0][$this->index]);
+    }
 }
diff --git a/src/holiday/LegalHoliday.php b/src/holiday/LegalHoliday.php
index b398f39..ceefbb3 100644
--- a/src/holiday/LegalHoliday.php
+++ b/src/holiday/LegalHoliday.php
@@ -72,21 +72,28 @@ function next(int $n): ?static
         }
         $index += $n;
         $y = $year;
-        $forward = $n > 0;
-        $add = $forward ? 1 : -1;
-        while ($forward ? ($index >= $size) : ($index < 0)) {
-            if ($forward) {
+        if ($n > 0) {
+            while ($index >= $size) {
                 $index -= $size;
+                $y += 1;
+                $size = 0;
+                if(preg_match_all(sprintf($reg, $y), static::$DATA, $matches)) {
+                    $size = count($matches[0]);
+                }
+                if ($size < 1) {
+                    return null;
+                }
             }
-            $y += $add;
-            $size = 0;
-            if(preg_match_all(sprintf($reg, $y), static::$DATA, $matches)) {
-                $size = count($matches[0]);
-            }
-            if ($size < 1) {
-                return null;
-            }
-            if (!$forward) {
+        } else {
+            while ($index < 0) {
+                $y -= 1;
+                $size = 0;
+                if(preg_match_all(sprintf($reg, $y), static::$DATA, $matches)) {
+                    $size = count($matches[0]);
+                }
+                if ($size < 1) {
+                    return null;
+                }
                 $index += $size;
             }
         }
diff --git a/src/lunar/LunarDay.php b/src/lunar/LunarDay.php
index 802d9e7..d977750 100644
--- a/src/lunar/LunarDay.php
+++ b/src/lunar/LunarDay.php
@@ -6,6 +6,7 @@
 use com\tyme\AbstractTyme;
 use com\tyme\culture\Direction;
 use com\tyme\culture\Duty;
+use com\tyme\culture\Element;
 use com\tyme\culture\fetus\FetusDay;
 use com\tyme\culture\God;
 use com\tyme\culture\Phase;
@@ -109,25 +110,7 @@ function __toString(): string
 
     function next(int $n): LunarDay
     {
-        if ($n == 0) {
-            return self::fromYmd($this->getYear(), $this->getMonth(), $this->day);
-        }
-        $d = $this->day + $n;
-        $m = $this->month;
-        $dayCount = $m->getDayCount();
-        $forward = $n > 0;
-        $add = $forward ? 1 : -1;
-        while ($forward ? ($d > $dayCount) : ($d <= 0)) {
-            if ($forward) {
-                $d -= $dayCount;
-            }
-            $m = $m->next($add);
-            $dayCount = $m->getDayCount();
-            if (!$forward) {
-                $d += $dayCount;
-            }
-        }
-        return self::fromYmd($m->getYear(), $m->getMonthWithLeap(), $d);
+        return $n == 0 ? self::fromYmd($this->getYear(), $this->getMonth(), $this->day) : $this->getSolarDay()->next($n)->getLunarDay();
     }
 
     /**
@@ -296,10 +279,7 @@ function getNineStar(): NineStar
     function getJupiterDirection(): Direction
     {
         $index = $this->getSixtyCycle()->getIndex();
-        if ($index % 12 < 6) {
-            return Direction::fromIndex([2, 8, 4, 6, 0][intdiv($index, 12)]);
-        }
-        return $this->month->getLunarYear()->getJupiterDirection();
+        return $index % 12 < 6 ? Element::fromIndex(intdiv($index, 12))->getDirection() : $this->month->getLunarYear()->getJupiterDirection();
     }
 
     /**
@@ -403,13 +383,4 @@ function getSixStar(): SixStar
     {
         return SixStar::fromIndex(($this->month->getMonth() + $this->day - 2) % 6);
     }
-
-    function equals(mixed $o): bool
-    {
-        if (!($o instanceof LunarDay)) {
-            return false;
-        }
-        return $this->month->equals($o->getMonth()) && $this->day == $o->getDay();
-    }
-
 }
diff --git a/src/lunar/LunarHour.php b/src/lunar/LunarHour.php
index d19520e..69c20bb 100644
--- a/src/lunar/LunarHour.php
+++ b/src/lunar/LunarHour.php
@@ -5,6 +5,7 @@
 
 use com\tyme\AbstractTyme;
 use com\tyme\culture\star\nine\NineStar;
+use com\tyme\culture\star\twelve\TwelveStar;
 use com\tyme\culture\Taboo;
 use com\tyme\eightchar\EightChar;
 use com\tyme\sixtycycle\EarthBranch;
@@ -262,6 +263,16 @@ function getSixtyCycle(): SixtyCycle
         return SixtyCycle::fromName(sprintf('%s%s', HeavenStem::fromIndex($heavenStemIndex)->getName(), EarthBranch::fromIndex($earthBranchIndex)->getName()));
     }
 
+    /**
+     * 黄道黑道十二神
+     *
+     * @return TwelveStar 黄道黑道十二神
+     */
+    function getTwelveStar(): TwelveStar
+    {
+        return TwelveStar::fromIndex($this->getSixtyCycle()->getEarthBranch()->getIndex() + (8 - $this->getDaySixtyCycle()->getEarthBranch()->getIndex() % 6) * 2);
+    }
+
     /**
      * 九星（时家紫白星歌诀：三元时白最为佳，冬至阳生顺莫差，孟日七宫仲一白，季日四绿发萌芽，每把时辰起甲子，本时星耀照光华，时星移入中宫去，顺飞八方逐细查。夏至阴生逆回首，孟归三碧季加六，仲在九宫时起甲，依然掌中逆轮跨。）
      *
@@ -319,12 +330,4 @@ function getAvoids(): array
     {
         return Taboo::getHourAvoids($this->getDaySixtyCycle(), $this->getSixtyCycle());
     }
-
-    function equals(mixed $o): bool
-    {
-        if (!($o instanceof LunarHour)) {
-            return false;
-        }
-        return $this->day->equals($o->getDay()) && $this->hour == $o->getHour() && $this->minute == $o->getMinute() && $this->second == $o->getSecond();
-    }
 }
diff --git a/src/lunar/LunarMonth.php b/src/lunar/LunarMonth.php
index 4f9937b..01a667f 100644
--- a/src/lunar/LunarMonth.php
+++ b/src/lunar/LunarMonth.php
@@ -22,6 +22,11 @@
  */
 class LunarMonth extends AbstractTyme
 {
+    /**
+     * @var array 缓存
+     */
+    private static array $cache = array();
+
     static array $NAMES = ['正月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月'];
 
 
@@ -55,58 +60,85 @@ class LunarMonth extends AbstractTyme
      */
     protected JulianDay $firstJulianDay;
 
-    protected function __construct(int $year, int $month)
+    protected function __construct(int $year, int $month, array $cache = null)
     {
-        $currentYear = LunarYear::fromYear($year);
-        $currentLeapMonth = $currentYear->getLeapMonth();
-        if ($month == 0 || $month > 12 || $month < -12) {
-            throw new InvalidArgumentException(sprintf('illegal lunar month: %d', $month));
-        }
-        $leap = $month < 0;
-        $m = abs($month);
-        if ($leap && $m != $currentLeapMonth) {
-            throw new InvalidArgumentException(sprintf('illegal leap month %d in lunar year %d', $m, $year));
-        }
+        if ($cache !== null) {
+            $m = (int)$cache[1];
+            $this->year = LunarYear::fromYear((int)$cache[0]);
+            $this->month = abs($m);
+            $this->leap = $m < 0;
+            $this->dayCount = (int)$cache[2];
+            $this->indexInYear = (int)$cache[3];
+            $this->firstJulianDay = JulianDay::fromJulianDay((double)$cache[4]);
+        } else {
+            $currentYear = LunarYear::fromYear($year);
+            $currentLeapMonth = $currentYear->getLeapMonth();
+            if ($month == 0 || $month > 12 || $month < -12) {
+                throw new InvalidArgumentException(sprintf('illegal lunar month: %d', $month));
+            }
+            $leap = $month < 0;
+            $m = abs($month);
+            if ($leap && $m != $currentLeapMonth) {
+                throw new InvalidArgumentException(sprintf('illegal leap month %d in lunar year %d', $m, $year));
+            }
 
-        // 冬至
-        $dongZhi = SolarTerm::fromIndex($year, 0);
-        $dongZhiJd = $dongZhi->getCursoryJulianDay();
+            // 冬至
+            $dongZhi = SolarTerm::fromIndex($year, 0);
+            $dongZhiJd = $dongZhi->getCursoryJulianDay();
 
-        // 冬至前的初一，今年首朔的日月黄经差
-        $w = ShouXingUtil::calcShuo($dongZhiJd);
-        if ($w > $dongZhiJd) {
-            $w -= 29.53;
-        }
+            // 冬至前的初一，今年首朔的日月黄经差
+            $w = ShouXingUtil::calcShuo($dongZhiJd);
+            if ($w > $dongZhiJd) {
+                $w -= 29.53;
+            }
 
-        // 正常情况正月初一为第3个朔日，但有些特殊的
-        $offset = 2;
-        if ($year > 8 && $year < 24) {
-            $offset = 1;
-        } else if (LunarYear::fromYear($year - 1)->getLeapMonth() > 10 && $year != 239 && $year != 240) {
-            $offset = 3;
-        }
+            // 正常情况正月初一为第3个朔日，但有些特殊的
+            $offset = 2;
+            if ($year > 8 && $year < 24) {
+                $offset = 1;
+            } else if (LunarYear::fromYear($year - 1)->getLeapMonth() > 10 && $year != 239 && $year != 240) {
+                $offset = 3;
+            }
 
-        // 位于当年的索引
-        $index = $m - 1;
-        if ($leap || ($currentLeapMonth > 0 && $m > $currentLeapMonth)) {
-            $index += 1;
+            // 位于当年的索引
+            $index = $m - 1;
+            if ($leap || ($currentLeapMonth > 0 && $m > $currentLeapMonth)) {
+                $index += 1;
+            }
+            $this->indexInYear = $index;
+
+            // 本月初一
+            $w += 29.5306 * ($offset + $index);
+            $firstDay = ShouXingUtil::calcShuo($w);
+            $this->firstJulianDay = JulianDay::fromJulianDay(JulianDay::J2000 + $firstDay);
+            // 本月天数 = 下月初一 - 本月初一
+            $this->dayCount = (int)(ShouXingUtil::calcShuo($w + 29.5306) - $firstDay);
+            $this->year = $currentYear;
+            $this->month = $m;
+            $this->leap = $leap;
         }
-        $this->indexInYear = $index;
-
-        // 本月初一
-        $w += 29.5306 * ($offset + $index);
-        $firstDay = ShouXingUtil::calcShuo($w);
-        $this->firstJulianDay = JulianDay::fromJulianDay(JulianDay::J2000 + $firstDay);
-        // 本月天数 = 下月初一 - 本月初一
-        $this->dayCount = (int)(ShouXingUtil::calcShuo($w + 29.5306) - $firstDay);
-        $this->year = $currentYear;
-        $this->month = $m;
-        $this->leap = $leap;
     }
 
     static function fromYm(int $year, int $month): static
     {
-        return new static($year, $month);
+        $c = null;
+        $key = sprintf("%d%d", $year, $month);
+        if (!empty(static::$cache[$key])) {
+            $c = static::$cache[$key];
+        }
+        if (null != $c) {
+            $m = new static(0, 0, $c);
+        } else {
+            $m = new static($year, $month);
+            static::$cache[$key] = [
+                $m->getYear(),
+                $m->getMonthWithLeap(),
+                $m->getDayCount(),
+                $m->getIndexInYear(),
+                $m->getFirstJulianDay()->getDay()
+            ];
+        }
+        return $m;
     }
 
     /**
@@ -233,18 +265,19 @@ function next(int $n): LunarMonth
         $m = $this->indexInYear + 1 + $n;
         $y = $this->year;
         $leapMonth = $y->getLeapMonth();
-        $monthSize = 12 + ($leapMonth > 0 ? 1 : 0);
-        $forward = $n > 0;
-        $add = $forward ? 1 : -1;
-        while ($forward ? ($m > $monthSize) : ($m <= 0)) {
-            if ($forward) {
-                $m -= $monthSize;
+        if ($n > 0) {
+            $monthCount = $leapMonth > 0 ? 13 : 12;
+            while ($m > $monthCount) {
+                $m -= $monthCount;
+                $y = $y->next(1);
+                $leapMonth = $y->getLeapMonth();
+                $monthCount = $leapMonth > 0 ? 13 : 12;
             }
-            $y = $y->next($add);
-            $leapMonth = $y->getLeapMonth();
-            $monthSize = 12 + ($leapMonth > 0 ? 1 : 0);
-            if (!$forward) {
-                $m += $monthSize;
+        } else {
+            while ($m <= 0) {
+                $y = $y->next(-1);
+                $leapMonth = $y->getLeapMonth();
+                $m += $leapMonth > 0 ? 13 : 12;
             }
         }
         $leap = false;
@@ -335,13 +368,4 @@ function getFetus(): FetusMonth
     {
         return FetusMonth::fromLunarMonth($this);
     }
-
-    function equals(mixed $o): bool
-    {
-        if (!($o instanceof LunarMonth)) {
-            return false;
-        }
-        return $this->getYear() == $o->getYear() && $this->getMonthWithLeap() == $o->getMonthWithLeap();
-    }
-
 }
diff --git a/src/lunar/LunarWeek.php b/src/lunar/LunarWeek.php
index 707a516..f90da1c 100644
--- a/src/lunar/LunarWeek.php
+++ b/src/lunar/LunarWeek.php
@@ -115,32 +115,29 @@ function __toString(): string
 
     function next(int $n): static
     {
+        $startIndex = $this->start->getIndex();
         if ($n == 0) {
-            return static::fromYm($this->getYear(), $this->getMonth(), $this->index, $this->start->getIndex());
+            return static::fromYm($this->getYear(), $this->getMonth(), $this->index, $startIndex);
         }
         $d = $this->index + $n;
         $m = $this->month;
-        $startIndex = $this->start->getIndex();
-        $weekCount = $m->getWeekCount($startIndex);
-        $forward = $n > 0;
-        $add = $forward ? 1 : -1;
-        while ($forward ? ($d >= $weekCount) : ($d < 0)) {
-            if ($forward) {
+        if ($n > 0) {
+            $weekCount = $m->getWeekCount($startIndex);
+            while ($d >= $weekCount) {
                 $d -= $weekCount;
-            } else {
+                $m = $m->next(1);
                 if (!LunarDay::fromYmd($m->getYear(), $m->getMonthWithLeap(), 1)->getWeek()->equals($this->start)) {
-                    $d += $add;
+                    $d += 1;
                 }
+                $weekCount = $m->getWeekCount($startIndex);
             }
-            $m = $m->next($add);
-            if ($forward) {
+        } else {
+            while ($d < 0) {
                 if (!LunarDay::fromYmd($m->getYear(), $m->getMonthWithLeap(), 1)->getWeek()->equals($this->start)) {
-                    $d += $add;
+                    $d -= 1;
                 }
-            }
-            $weekCount = $m->getWeekCount($startIndex);
-            if (!$forward) {
-                $d += $weekCount;
+                $m = $m->next(-1);
+                $d += $m->getWeekCount($startIndex);
             }
         }
         return static::fromYm($m->getYear(), $m->getMonthWithLeap(), $d, $startIndex);
@@ -173,4 +170,12 @@ function getDays(): array
         return $l;
     }
 
+    /**
+     * @param mixed $o 对象
+     * @return bool true/false
+     */
+    function equals(mixed $o): bool
+    {
+        return $o instanceof LunarWeek && $this->getFirstDay() . $this->equals($o->getFirstDay());
+    }
 }
diff --git a/src/lunar/LunarYear.php b/src/lunar/LunarYear.php
index b7cda5d..f1a9cc0 100644
--- a/src/lunar/LunarYear.php
+++ b/src/lunar/LunarYear.php
@@ -94,6 +94,16 @@ function getDayCount(): int
         return $n;
     }
 
+    /**
+     * 月数
+     *
+     * @return int 月数
+     */
+    function getMonthCount(): int
+    {
+        return $this->getLeapMonth() > 0 ? 13 : 12;
+    }
+
     /**
      * 依据国家标准《农历的编算和颁行》GB/T 33661-2017，农历年有2种命名方法：干支纪年法和生肖纪年法，这里默认采用干支纪年法。
      *
@@ -176,16 +186,10 @@ function getMonths(): array
     {
         $l = array();
         $m = LunarMonth::fromYm($this->year, 1);
-        while ($m->getYear()->getYear() == $this->year) {
+        while ($m->getYear() == $this->year) {
             $l[] = $m;
             $m = $m->next(1);
         }
         return $l;
     }
-
-    function equals(mixed $o): bool
-    {
-        return $o instanceof LunarYear && $o->getYear() == $this->year;
-    }
-
 }
diff --git a/src/sixtycycle/EarthBranch.php b/src/sixtycycle/EarthBranch.php
index 58aa714..631d501 100644
--- a/src/sixtycycle/EarthBranch.php
+++ b/src/sixtycycle/EarthBranch.php
@@ -116,7 +116,7 @@ function getDirection(): Direction
     }
 
     /**
-     * 相冲的地支（子午冲，丑未冲，寅申冲，辰戌冲，卯酉冲，巳亥冲）
+     * 六冲（子午冲，丑未冲，寅申冲，辰戌冲，卯酉冲，巳亥冲）
      *
      * @return EarthBranch 地支
      */
@@ -125,6 +125,36 @@ function getOpposite(): static
         return $this->next(6);
     }
 
+    /**
+     * 六合（子丑合，寅亥合，卯戌合，辰酉合，巳申合，午未合）
+     *
+     * @return EarthBranch 地支
+     */
+    function getCombine(): static
+    {
+        return $this->fromIndex(1 - $this->index);
+    }
+
+    /**
+     * 合化（子丑合化土，寅亥合化木，卯戌合化火，辰酉合化金，巳申合化水，午未合化土）
+     * @param EarthBranch $target 地支
+     * @return Element|null 五行，如果无法合化，返回null
+     */
+    function combine(EarthBranch $target): ?Element
+    {
+        return $this->getCombine()->equals($target) ? Element::fromIndex([2, 2, 0, 1, 3, 4, 2, 2, 4, 3, 1, 0][$this->index]) : null;
+    }
+
+    /**
+     * 六害（子未害、丑午害、寅巳害、卯辰害、申亥害、酉戌害）
+     *
+     * @return EarthBranch 地支
+     */
+    function getHarm(): static
+    {
+        return $this->fromIndex(19 - $this->index);
+    }
+
     /**
      * 煞（逢巳日、酉日、丑日必煞东；亥日、卯日、未日必煞西；申日、子日、辰日必煞南；寅日、午日、戌日必煞北。）
      *
diff --git a/src/sixtycycle/HeavenStem.php b/src/sixtycycle/HeavenStem.php
index 4784eb8..77afa42 100644
--- a/src/sixtycycle/HeavenStem.php
+++ b/src/sixtycycle/HeavenStem.php
@@ -95,7 +95,7 @@ function getTenStar(HeavenStem $target): TenStar
      */
     function getDirection(): Direction
     {
-        return Direction::fromIndex([2, 8, 4, 6, 0][intdiv($this->index, 2)]);
+        return $this->getElement()->getDirection();
     }
 
     /**
@@ -169,4 +169,24 @@ function getTerrain(EarthBranch $earthBranch): Terrain
         $earthBranchIndex = $earthBranch->getIndex();
         return Terrain::fromIndex([1, 6, 10, 9, 10, 9, 7, 0, 4, 3][$this->index] + (YinYang::YANG == $this->getYinYang() ? $earthBranchIndex : -$earthBranchIndex));
     }
+
+    /**
+     * 五合（甲己合，乙庚合，丙辛合，丁壬合，戊癸合）
+     *
+     * @return HeavenStem 天干
+     */
+    function getCombine(): static
+    {
+        return $this->next(5);
+    }
+
+    /**
+     * 合化（甲己合化土，乙庚合化金，丙辛合化水，丁壬合化木，戊癸合化火）
+     * @param HeavenStem $target 天干
+     * @return Element|null 五行，如果无法合化，返回null
+     */
+    function combine(HeavenStem $target): ?Element
+    {
+        return $this->getCombine()->equals($target) ? Element::fromIndex($this->index + 2) : null;
+    }
 }
diff --git a/src/solar/SolarDay.php b/src/solar/SolarDay.php
index 81d83e2..24efc6e 100644
--- a/src/solar/SolarDay.php
+++ b/src/solar/SolarDay.php
@@ -402,7 +402,7 @@ function getLunarDay(): LunarDay
         $days = $this->subtract($m->getFirstJulianDay()->getSolarDay());
         while ($days < 0) {
             $m = $m->next(-1);
-            $days = $this->subtract($m->getFirstJulianDay()->getSolarDay());
+            $days += $m->getDayCount();
         }
         return LunarDay::fromYmd($m->getYear(), $m->getMonthWithLeap(), $days + 1);
     }
diff --git a/src/solar/SolarHalfYear.php b/src/solar/SolarHalfYear.php
index 461e41a..b43b91a 100644
--- a/src/solar/SolarHalfYear.php
+++ b/src/solar/SolarHalfYear.php
@@ -101,8 +101,8 @@ function getMonths(): array
     {
         $l = array();
         $y = $this->getYear();
-        for ($i = 0; $i < 6; $i++) {
-            $l[] = SolarMonth::fromYm($y, $this->index * 6 + $i + 1);
+        for ($i = 1; $i < 7; $i++) {
+            $l[] = SolarMonth::fromYm($y, $this->index * 6 + $i);
         }
         return $l;
     }
diff --git a/src/solar/SolarMonth.php b/src/solar/SolarMonth.php
index 7373fbc..9045084 100644
--- a/src/solar/SolarMonth.php
+++ b/src/solar/SolarMonth.php
@@ -173,8 +173,8 @@ function getDays(): array
         $size = $this->getDayCount();
         $y = $this->getYear();
         $l = array();
-        for ($i = 0; $i < $size; $i++) {
-            $l[] = SolarDay::fromYmd($y, $this->month, $i + 1);
+        for ($i = 1; $i <= $size; $i++) {
+            $l[] = SolarDay::fromYmd($y, $this->month, $i);
         }
         return $l;
     }
diff --git a/src/solar/SolarSeason.php b/src/solar/SolarSeason.php
index 8ac8544..608c42d 100644
--- a/src/solar/SolarSeason.php
+++ b/src/solar/SolarSeason.php
@@ -101,8 +101,8 @@ function getMonths(): array
     {
         $l = array();
         $y = $this->getYear();
-        for ($i = 0; $i < 3; $i++) {
-            $l[] = SolarMonth::fromYm($y, $this->index * 3 + $i + 1);
+        for ($i = 1; $i < 4; $i++) {
+            $l[] = SolarMonth::fromYm($y, $this->index * 3 + $i);
         }
         return $l;
     }
diff --git a/src/solar/SolarWeek.php b/src/solar/SolarWeek.php
index a71344e..0558aaf 100644
--- a/src/solar/SolarWeek.php
+++ b/src/solar/SolarWeek.php
@@ -101,9 +101,10 @@ function getIndex(): int
     function getIndexInYear(): int
     {
         $i = 0;
+        $firstDay = $this->getFirstDay();
         // 今年第1周
         $w = self::fromYm($this->getYear(), 1, 0, $this->start->getIndex());
-        while (!$w->equals($this)) {
+        while (!$w->getFirstDay()->equals($firstDay)) {
             $w = $w->next(1);
             $i += 1;
         }
@@ -132,32 +133,29 @@ function __toString(): string
 
     function next(int $n): static
     {
+        $startIndex = $this->start->getIndex();
         if ($n == 0) {
-            return static::fromYm($this->getYear(), $this->getMonth(), $this->index, $this->start->getIndex());
+            return static::fromYm($this->getYear(), $this->getMonth(), $this->index, $startIndex);
         }
         $d = $this->index + $n;
         $m = $this->month;
-        $startIndex = $this->start->getIndex();
-        $weekCount = $m->getWeekCount($startIndex);
-        $forward = $n > 0;
-        $add = $forward ? 1 : -1;
-        while ($forward ? ($d >= $weekCount) : ($d < 0)) {
-            if ($forward) {
+        if ($n > 0) {
+            $weekCount = $m->getWeekCount($startIndex);
+            while ($d >= $weekCount) {
                 $d -= $weekCount;
-            } else {
+                $m = $m->next(1);
                 if (!SolarDay::fromYmd($m->getYear(), $m->getMonth(), 1)->getWeek()->equals($this->start)) {
-                    $d += $add;
+                    $d += 1;
                 }
+                $weekCount = $m->getWeekCount($startIndex);
             }
-            $m = $m->next($add);
-            if ($forward) {
+        } else {
+            while ($d < 0) {
                 if (!SolarDay::fromYmd($m->getYear(), $m->getMonth(), 1)->getWeek()->equals($this->start)) {
-                    $d += $add;
+                    $d -= 1;
                 }
-            }
-            $weekCount = $m->getWeekCount($startIndex);
-            if (!$forward) {
-                $d += $weekCount;
+                $m = $m->next(-1);
+                $d += $m->getWeekCount($startIndex);
             }
         }
         return static::fromYm($m->getYear(), $m->getMonth(), $d, $startIndex);
@@ -190,4 +188,12 @@ function getDays(): array
         return $l;
     }
 
+    /**
+     * @param mixed $o 对象
+     * @return bool true/false
+     */
+    function equals(mixed $o): bool
+    {
+        return $o instanceof SolarWeek && $this->getFirstDay().$this->equals($o->getFirstDay());
+    }
 }
diff --git a/src/solar/SolarYear.php b/src/solar/SolarYear.php
index e2acdab..8a79be8 100644
--- a/src/solar/SolarYear.php
+++ b/src/solar/SolarYear.php
@@ -84,8 +84,8 @@ function next(int $n): static
     function getMonths(): array
     {
         $l = array();
-        for ($i = 0; $i < 12; $i++) {
-            $l[] = SolarMonth::fromYm($this->year, $i + 1);
+        for ($i = 1; $i < 13; $i++) {
+            $l[] = SolarMonth::fromYm($this->year, $i);
         }
         return $l;
     }