refactor 210

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_210.java

@@ -1,60 +0,0 @@
-package com.fishercoder.solutions;
-
-import java.util.HashSet;
-import java.util.Iterator;
-import java.util.LinkedList;
-import java.util.Queue;
-import java.util.Set;
-
-public class _210 {
-
-    public static class Solution1 {
-        public int[] findOrder(int numCourses, int[][] prerequisites) {
-            int[] inDegree = new int[numCourses];
-            for (int[] course : prerequisites) {
-                inDegree[course[0]]++;
-            }
-
-            Set<Integer> zeroDegree = new HashSet();
-            Queue<Integer> queue = new LinkedList();
-            for (int i = 0; i < numCourses; i++) {
-                if (inDegree[i] == 0) {
-                    zeroDegree.add(i);
-                    queue.offer(i);
-                }
-            }
-
-            if (zeroDegree.isEmpty()) {
-                return new int[0];
-            }
-
-            while (!zeroDegree.isEmpty()) {
-                Iterator<Integer> it = zeroDegree.iterator();
-                int course = it.next();
-                zeroDegree.remove(course);
-                for (int[] pre : prerequisites) {
-                    if (course == pre[1]) {
-                        inDegree[pre[0]]--;
-                        if (inDegree[pre[0]] == 0) {
-                            zeroDegree.add(pre[0]);
-                            queue.offer(pre[0]);
-                        }
-                    }
-                }
-            }
-
-            for (int i = 0; i < numCourses; i++) {
-                if (inDegree[i] != 0) {
-                    return new int[0];
-                }
-            }
-
-            int[] result = new int[queue.size()];
-            int i = 0;
-            while (!queue.isEmpty()) {
-                result[i++] = queue.poll();
-            }
-            return result;
-        }
-    }
-}