From d59fa6d515b6465bdfc8c22f22ca73dda09f5bfa Mon Sep 17 00:00:00 2001
From: algorithmzuo <algorithmzuo@163.com>
Date: Thu, 25 Mar 2021 23:11:56 +0800
Subject: [PATCH] modify code

---
 src/class43/Code03_PavingTile.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/class43/Code03_PavingTile.java b/src/class43/Code03_PavingTile.java
index 4a7ce01..c4bf363 100644
--- a/src/class43/Code03_PavingTile.java
+++ b/src/class43/Code03_PavingTile.java
@@ -148,7 +148,7 @@ public class Code03_PavingTile {
 		}
 		int ans = 0;
 		ans += dfs3(op, col - 1, level, N, M, dp);
-		if ((op & (1 << col)) == 0 && col - 1 >= 0 && (op & (1 << (col - 1))) == 0) {
+		if (col > 0 && (op & (3 << (col - 1))) == 0) {
 			ans += dfs3((op | (3 << (col - 1))), col - 2, level, N, M, dp);
 		}
 		return ans;