fix merge

app/src/main/java/sudoku/Cell.java

@@ -1,7 +1,5 @@
 package sudoku;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
-
 public abstract class Cell {
 
 	protected static int NOSYMBOLE = -1;
@@ -32,11 +30,8 @@ public abstract class Cell {
 		this.block = block;
 	}
 
-	@Override
-	public boolean equals(Object obj) {
-		if (obj instanceof Cell otherCell)
-			return otherCell.getSymbolIndex() == this.getSymbolIndex();
-		return false;
+	public boolean equalsValue(Cell otherCell) {
+		return otherCell.getSymbolIndex() == this.getSymbolIndex();
 	}
 
 	@Override