延迟走法采用更加激进的裁剪策略

PikaCat-OuO · Apr 27, 2022 · 4946785 · 4946785
1 parent dca90c3
commit 4946785
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Showing 2 changed files with 28 additions and 13 deletions.
diff --git a/ChineseChess.pro.user b/ChineseChess.pro.user
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE QtCreatorProject>
-<!-- Written by QtCreator 7.0.0, 2022-04-27T13:10:34. -->
+<!-- Written by QtCreator 7.0.0, 2022-04-27T16:10:25. -->
 <qtcreator>
  <data>
   <variable>EnvironmentId</variable>

diff --git a/src/search/searchinstance.cpp b/src/search/searchinstance.cpp
@@ -13,7 +13,7 @@ void SearchInstance::searchRoot(const qint8 depth) {
                        this->m_killerTable.getKiller(this->m_distance, 1)};
 
   qint16 bestScore { LOSS_SCORE };
-  // LMR的计数器
+  // LMR/LMP的计数器
   quint8 moveSearched { 0 };
   this->m_legalMove = 0;
   // 是否被对方将军
@@ -32,13 +32,20 @@ void SearchInstance::searchRoot(const qint8 depth) {
       if (moveSearched == 0) {
         tryScore = -searchFull(LOSS_SCORE, MATE_SCORE, newDepth, NO_NULL);
       } else {
-        // LMR，要求当前层数大于等于3，没有被将军，该步不是吃子步，从第4步棋开始往后
-        if (moveSearched >= 4 and depth >= 3 and notInCheck and
-            newDepth not_eq depth and not lastMove.isCapture()) {
-          tryScore = -searchFull(-bestScore - 1, -bestScore, newDepth - 1);
+        // 保证搜索正常进行
+        tryScore = bestScore + 1;
+        // LMR/LMP，要求没有被将军，该步不是吃子步
+        if (notInCheck and newDepth not_eq depth and not lastMove.isCapture()) {
+          // LMR，在层数大于等于3时使用
+          if (depth >= 3) {
+            qint8 reduce = 1;
+            // 靠后的走法采用更加激进的裁剪策略
+            if (moveSearched >= 6) reduce = depth / 3;
+            tryScore = -searchFull(-bestScore - 1, -bestScore, newDepth - reduce);
+          }
+          // LMP，在层数小于3时使用，要求已经搜索过了一定数量的走法
+          else if (moveSearched > 6 * depth) tryScore = LOSS_SCORE;
         }
-        // 其余情况保证搜索正常进行
-        else tryScore = bestScore + 1;
         if (tryScore > bestScore) {
           tryScore = -searchFull(-bestScore - 1, -bestScore, newDepth);
           if (tryScore > bestScore) {
@@ -166,7 +173,7 @@ qint16 SearchInstance::searchFull(qint16 alpha, const qint16 beta,
   qint16 bestScore { LOSS_SCORE };
   Move bestMove { };
 
-  // LMR的计数器
+  // LMR/LMP的计数器
   quint8 moveSearched { 0 };
   // 遍历所有走法
   while ((move = search.getNextMove()).isVaild()) {
@@ -179,10 +186,18 @@ qint16 SearchInstance::searchFull(qint16 alpha, const qint16 beta,
       // PVS
       if (moveSearched == 0) tryScore = -searchFull(-beta, -alpha, newDepth);
       else {
-        // LMR，要求当前层数大于等于3，没有被将军，没有将军别人，该步不是吃子步，从第4步棋开始往后
-        if (moveSearched >= 4 and depth >= 3 and notInCheck and
-            newDepth not_eq depth and not lastMove.isCapture()) {
-          tryScore = -searchFull(-alpha - 1, -alpha, newDepth - 1);
+        // 保证搜索正常进行
+        tryScore = alpha + 1;
+        // LMR/LMP，要求没有被将军，该步不是吃子步
+        if (notInCheck and newDepth not_eq depth and not lastMove.isCapture()) {
+          // LMR，在层数大于等于3时使用
+          if (depth >= 3) {
+            qint8 reduce = 1;
+            if (moveSearched >= 6) reduce = depth / 3;
+            tryScore = -searchFull(-alpha - 1, -alpha, newDepth - reduce);
+          }
+          // LMP，在层数小于3时使用，要求已经搜索过了一定数量的走法
+          else if (moveSearched > 6 * depth) tryScore = LOSS_SCORE;
         }
         // 其余情况保证搜索正常进行
         else tryScore = alpha + 1;