diff --git a/src/main/java/com/code/leet/Fall2021.java b/src/main/java/com/code/leet/Fall2021.java
new file mode 100644
index 0000000..4d28be5
--- /dev/null
+++ b/src/main/java/com/code/leet/Fall2021.java
@@ -0,0 +1,171 @@
+package com.code.leet;
+
+import com.code.leet.entiy.TwoArray;
+import javafx.util.Pair;
+
+import java.util.*;
+
+/**
+ * @description:
+ * @author: Administrator
+ * @date: 2021/9/11-15:06
+ */
+public class Fall2021 {
+    public int minimumSwitchingTimes(int[][] source, int[][] target) {
+        Map<Integer, Integer> map = new HashMap<>();
+        for (int i = 0; i < source.length; i++) {
+            for (int j = 0; j < source[0].length; j++) {
+                map.put(source[i][j], map.getOrDefault(source[i][j], 0) + 1);
+            }
+        }
+        int count = 0;
+        for (int i = 0; i < target.length; i++) {
+            for (int j = 0; j < target[0].length; j++) {
+                map.put(target[i][j], map.getOrDefault(target[i][j], 0) - 1);
+                if (map.get(target[i][j]) < 0) {
+                    count++;
+                    map.put(target[i][j], 0);
+                }
+            }
+        }
+        return count;
+    }
+
+    public int maxmiumScore(int[] cards, int cnt) {
+        Arrays.sort(cards);
+        int size = cards.length;
+        int i = size - 1;
+        if (cnt == 1) {
+            for (; i >= 0; i--) {
+                if (cards[i] % 2 == 0) {
+                    return cards[i];
+                }
+            }
+            return 0;
+        }
+        int sum = 0;
+        int o1 = cards[i];
+        int o2 = 0;
+        int d1 = cards[i];
+        int d2 = 0;
+        for (; i >= size - cnt; i--) {
+            sum += cards[i];
+            if (cards[i] % 2 == 0) {
+                d1 = Math.min(d1, cards[i]);
+            } else {
+                o1 = Math.min(o1, cards[i]);
+            }
+        }
+        if (sum % 2 == 0) {
+            return sum;
+        }
+        boolean oo = true;
+        boolean dd = true;
+        for (; i >= 0; i--) {
+            if (dd && cards[i] % 2 == 0) {
+                d2 = cards[i];
+                dd = false;
+            }
+            if (oo && cards[i] % 2 == 1) {
+                o2 = cards[i];
+                oo = false;
+            }
+            if (!(oo && dd)) {
+                break;
+            }
+        }
+        if (o2 == 0 && d2 == 0) {
+            return 0;
+        } else if (o2 != 0 && d2 == 0) {
+            return sum - d1 + o2;
+        } else if (o2 == 0) {
+            return sum - o1 + d2;
+        } else {
+            return sum - o1 - d1 + Math.max(o1 + o2, d1 + d2);
+        }
+    }
+
+    public static void main(String[] args) {
+        Fall2021 fall2021 = new Fall2021();
+        TwoArray twoArray = new TwoArray("[[3,3,1],[3,2,1]]", true);
+        int[][] toys = twoArray.getArr();
+        twoArray = new TwoArray("[[4,3]]", true);
+        int[][] circles = twoArray.getArr();
+        System.out.println(fall2021.circleGame(toys, circles, 2));
+    }
+
+    public int circleGame(int[][] toys, int[][] circles, int r) {
+        List<Integer> list = new ArrayList<>();
+        for (int i = 0; i < toys.length; i++) {
+            if (toys[i][2] <= r) {
+                list.add(i);
+            }
+        }
+        int count = 0;
+        for (int[] circle : circles) {
+            if (list.size() == 0) {
+                break;
+            }
+            for (int i = list.size() - 1; i >= 0; i--) {
+                if (isIn(toys[list.get(i)][0], toys[list.get(i)][1], circle[0], circle[1], r, toys[list.get(i)][2])) {
+                    count++;
+                    list.remove(i);
+                }
+            }
+        }
+        return count;
+    }
+
+    private boolean isIn(int x1, int y1, int x2, int y2, int r, int c) {
+        int x = x1 - x2;
+        int y = y1 - y2;
+        long m = (long) x * x + (long) y * y;
+        double l = Math.sqrt(m) + c;
+        return l <= r;
+    }
+
+//    public int circleGame(int[][] toys, int[][] circles, int r) {
+//        List<List<Pair<Integer, Integer>>> lists = new ArrayList<>();
+//        for (int[] toy : toys) {
+//            if (toy[2] > r) {
+//                continue;
+//            }
+//            List<Pair<Integer, Integer>> list = new ArrayList<>();
+//            list.add(new Pair<>(toy[0] - toy[2], toy[1]));
+//            list.add(new Pair<>(toy[0] + toy[2], toy[1]));
+//            list.add(new Pair<>(toy[0], toy[1] - toy[2]));
+//            list.add(new Pair<>(toy[0], toy[1] + toy[2]));
+//            lists.add(new ArrayList<>(list));
+//        }
+//        int count = 0;
+//        for (int[] circle : circles) {
+//            if (lists.size() == 0) {
+//                break;
+//            }
+//            for (int i = lists.size() - 1; i >= 0; i--) {
+//                List<Pair<Integer, Integer>> list = lists.get(i);
+//                boolean bl = true;
+//                for (Pair<Integer, Integer> pair : list) {
+//                    if (!isIn(circle[0], circle[1], pair.getKey(), pair.getValue(), r)) {
+//                        bl = false;
+//                        break;
+//                    }
+//                }
+//                if (bl) {
+//                    count++;
+//                    lists.remove(i);
+//                }
+//            }
+//        }
+//        return count;
+//    }
+//
+//    private boolean isIn(int x1, int y1, int x2, int y2, int r) {
+//        int x = x1 - x2;
+//        int y = y1 - y2;
+//        long m = (long) x * x + (long) y * y;
+//        long n = (long) r * r;
+//        return m <= n;
+//    }
+
+}