From 5eb5ef246df40afcc30bfed0f005071e6983c98f Mon Sep 17 00:00:00 2001
From: Christoph Zengler <christoph.zengler@booleworks.com>
Date: Sun, 4 Feb 2024 20:43:35 +0100
Subject: [PATCH] Equals/Hashcode for DNNF data structure

---
 .../dnnf/datastructures/Dnnf.java             | 20 ++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/logicng/knowledgecompilation/dnnf/datastructures/Dnnf.java b/src/main/java/org/logicng/knowledgecompilation/dnnf/datastructures/Dnnf.java
index 4a2dea46..1b2f964b 100644
--- a/src/main/java/org/logicng/knowledgecompilation/dnnf/datastructures/Dnnf.java
+++ b/src/main/java/org/logicng/knowledgecompilation/dnnf/datastructures/Dnnf.java
@@ -32,11 +32,12 @@
 import org.logicng.formulas.Variable;
 import org.logicng.knowledgecompilation.dnnf.functions.DnnfFunction;
 
+import java.util.Objects;
 import java.util.SortedSet;
 
 /**
  * A DNNF - Decomposable Negation Normal Form.
- * @version 2.0.0
+ * @version 2.5.0
  * @since 2.0.0
  */
 public final class Dnnf {
@@ -79,4 +80,21 @@ public Formula formula() {
     public SortedSet<Variable> getOriginalVariables() {
         return this.originalVariables;
     }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        final Dnnf dnnf = (Dnnf) o;
+        return Objects.equals(this.originalVariables, dnnf.originalVariables) && Objects.equals(this.formula, dnnf.formula);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(this.originalVariables, this.formula);
+    }
 }