From 74327b8c3bfaeb4a02a60fbfb08f2320d1312543 Mon Sep 17 00:00:00 2001
From: huangge1199 <huangge1199@hotmail.com>
Date: Fri, 2 Jul 2021 16:06:53 +0800
Subject: [PATCH] =?UTF-8?q?LeetBook--=E9=98=9F=E5=88=97&=E6=A0=88--01=20?=
 =?UTF-8?q?=E7=9F=A9=E9=98=B5?=
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---
 .../leet/book/queueStack/UpdateMatrix.java    | 52 +++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 src/main/java/leet/book/queueStack/UpdateMatrix.java

diff --git a/src/main/java/leet/book/queueStack/UpdateMatrix.java b/src/main/java/leet/book/queueStack/UpdateMatrix.java
new file mode 100644
index 0000000..d8a57b4
--- /dev/null
+++ b/src/main/java/leet/book/queueStack/UpdateMatrix.java
@@ -0,0 +1,52 @@
+package leet.book.queueStack;
+
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Queue;
+
+/**
+ * Created with IntelliJ IDEA.
+ *
+ * @author: 轩辕龙儿
+ * @date: 2021/7/2 15:49
+ * @Description: No Description
+ */
+public class UpdateMatrix {
+    public static void main(String[] args) {
+        Solution solution = new UpdateMatrix().new Solution();
+    }
+
+    class Solution {
+        public int[][] updateMatrix(int[][] mat) {
+            Queue<int[]> queue = new LinkedList<>();
+            int xLength = mat.length;
+            int yLength = mat[0].length;
+            boolean[][] use = new boolean[xLength][yLength];
+            for (int i = 0; i < xLength; i++) {
+                for (int j = 0; j < yLength; j++) {
+                    if (mat[i][j] == 0) {
+                        queue.offer(new int[]{i, j});
+                        use[i][j] = true;
+                    }
+                }
+            }
+            int[][] ops = {{-1, 0}, {1, 0}, {0, -1}, {0, 1}};
+            while (!queue.isEmpty()) {
+                int[] temp = queue.poll();
+                int x = temp[0];
+                int y = temp[1];
+                for (int[] op : ops) {
+                    int tx = x + op[0];
+                    int ty = y + op[1];
+                    if (tx >= 0 && tx < xLength && ty >= 0 && ty < yLength && !use[tx][ty]) {
+                        mat[tx][ty] = mat[x][y] + 1;
+                        queue.offer(new int[]{tx,ty});
+                        use[tx][ty]=true;
+                    }
+                }
+            }
+            return mat;
+        }
+    }
+}