diff --git a/src/backend/Board.java b/src/backend/Board.java
index 3bb29b0..02dd053 100644
--- a/src/backend/Board.java
+++ b/src/backend/Board.java
@@ -267,14 +267,47 @@ public class Board {
 		return x >= 0 && y >= 0 && x < colNum && y < lineNum;
 	}
 
-	// other methods not changed
-	public String[] toFileRep() { 
-		//TODO
-		return null; 
+	// PART3
+	public String[] toFileRep() {
+	    String[] result = new String[lineNum + 1]; // One line per row + 1 for turn
+	    for (int y = 0; y < lineNum; y++) {
+	        StringBuilder sb = new StringBuilder();
+	        for (int x = 0; x < colNum; x++) {
+	            if (x > 0) sb.append(",");
+	            Piece piece = board[y][x];
+	            if (piece != null) {
+	                sb.append(piece.isWhite() ? "W" : "B");
+	                sb.append(piece.getType().getSummary()); // Ensure this returns K/Q/R/N/B/P
+	            }
+	        }
+	        result[y] = sb.toString();
+	    }
+	    result[lineNum] = isWhiteTurn ? "W" : "B";
+	    return result;
 	}
+	
+	
 	public Board(String[] array) {
-		//TODO
+	    this.colNum = 8;
+	    this.lineNum = 8;
+	    this.board = new Piece[lineNum][colNum];
+
+	    for (int y = 0; y < lineNum; y++) {
+	        String[] tokens = array[y].split(",", -1);
+	        for (int x = 0; x < colNum; x++) {
+	            String token = tokens[x].trim();
+	            if (token.length() == 2) {
+	                boolean isWhite = token.charAt(0) == 'W';
+	                char typeChar = token.charAt(1);
+	                PieceType type = PieceType.fromSummary(typeChar); // You must implement this method
+	                board[y][x] = new Piece(x, y, type, isWhite);
+	            }
+	        }
+	    }
+	    this.isWhiteTurn = array[lineNum].equalsIgnoreCase("W");
 	}
+	
+	
 	public void undoLastMove() {
 		//TODO
 	}