ADD file via upload

src/PowerManager.java

@@ -0,0 +1,95 @@
+import java.util.List;
+import java.util.Random;
+
+/**
+ * 负责添加幂运算
+ */
+public class PowerManager {
+  private static final Random RANDOM = new Random();
+  
+  // 普通幂运算
+  public String addPowerOperations(String expression, List<Integer> numPositions) {
+    if (numPositions.isEmpty()) return expression;
+    
+    String[] tokens = expression.split(" ");
+    int targetIndex = chooseTargetIndex(tokens, numPositions, null);
+    
+    if (targetIndex != -1) {
+      tokens[targetIndex] = applyPower(tokens[targetIndex], tokens, targetIndex);
+    }
+    
+    return String.join(" ", tokens);
+  }
+  
+  // 避免加在 trig 已占用的位置，同时避免加在运算符右边
+  public String addPowerOperationsAvoid(String expression, List<Integer> numPositions, List<Integer> trigPositions) {
+    if (numPositions.isEmpty()) return expression;
+    
+    String[] tokens = expression.split(" ");
+    int targetIndex = chooseTargetIndex(tokens, numPositions, trigPositions);
+    
+    if (targetIndex != -1) {
+      tokens[targetIndex] = applyPower(tokens[targetIndex], tokens, targetIndex);
+    }
+    
+    return String.join(" ", tokens);
+  }
+  
+  // 选择合适的位置加幂运算
+  private int chooseTargetIndex(String[] tokens, List<Integer> numPositions, List<Integer> avoidPositions) {
+    for (int tries = 0; tries < 20; tries++) {
+      int idx = numPositions.get(RANDOM.nextInt(numPositions.size()));
+      
+      if ((avoidPositions == null || !avoidPositions.contains(idx)) && canApplyPower(tokens, idx)) {
+        return idx;
+      }
+    }
+    return -1;
+  }
+  
+  // 检查该位置是否可以加幂运算
+  private boolean canApplyPower(String[] tokens, int index) {
+    if (!isNumber(tokens[index])) return false;
+    if (tokens[index].contains("^") || tokens[index].contains("√")) return false; // 避免重复幂运算
+    
+    // 不能加在运算符右边
+    if (index > 0) {
+      String prev = tokens[index - 1];
+      if (prev.equals("/") || prev.equals("*") || prev.equals("+") || prev.equals("-")) {
+        return false;
+      }
+    }
+    return true;
+  }
+  
+  // 应用平方或开方（根号放左括号左侧，平方放右括号右侧）
+  private String applyPower(String token, String[] tokens, int index) {
+    boolean useSqrt = RANDOM.nextBoolean();
+    
+    if (useSqrt) {
+      // 根号放在左括号左侧，如果前面是左括号，则放在括号左边
+      if (index > 0 && tokens[index - 1].equals(")")) {
+        return "√" + token; // 特殊情况，仍然放数字前
+      }
+      if (index > 0 && tokens[index - 1].equals("(")) {
+        return "√" + token;
+      }
+      return "√" + token;
+    } else {
+      // 平方放在右括号右侧，如果后面是右括号，则放在括号右边
+      if (index < tokens.length - 1 && tokens[index + 1].equals(")")) {
+        return token + "^2";
+      }
+      return token + "^2";
+    }
+  }
+  
+  private boolean isNumber(String token) {
+    try {
+      Integer.parseInt(token);
+      return true;
+    } catch (NumberFormatException e) {
+      return false;
+    }
+  }
+}