add

5.leetcode/src/com/fanxb/common/Q54.java

@@ -0,0 +1,61 @@
+package com.fanxb.common;
+
+import java.util.LinkedList;
+import java.util.List;
+
+/**
+ * Created with IntelliJ IDEA
+ *
+ * @author fanxb
+ * Date: 2020/6/9 15:10
+ */
+public class Q54 {
+    public List<Integer> spiralOrder(int[][] matrix) {
+        List<Integer> list = new LinkedList<>();
+        list.add(matrix[0][0]);
+        int i = 0, j = 0, count = 1, m = matrix.length, n = matrix[0].length;
+        int type = 0;
+        matrix[0][0] = -200;
+        while (count < m * n) {
+            switch (type) {
+                //向右走
+                case 0:
+                    if (j + 1 >= n || matrix[i][j + 1] == -200) {
+                        type = 1;
+                        continue;
+                    } else j++;
+                    break;
+                //向下
+                case 1:
+                    if (i + 1 >= m || matrix[i + 1][j] == -200) {
+                        type = 2;
+                        continue;
+                    } else i++;
+                    break;
+                //向左
+                case 2:
+                    if (j - 1 == -1 || matrix[i][j - 1] == -200) {
+                        type = 3;
+                        continue;
+                    } else j--;
+                    break;
+                //向上
+                case 3:
+                    if (i - 1 == -1 || matrix[i - 1][j] == -200) {
+                        type = 0;
+                        continue;
+                    } else i--;
+                    break;
+            }
+            list.add(matrix[i][j]);
+            matrix[i][j] = -200;
+            count++;
+        }
+        return list;
+    }
+
+
+    public static void main(String[] args) {
+        System.out.printf(new Q54().spiralOrder(new int[][]{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}).toString());
+    }
+}