diff --git a/src/main/java/com/code/leet/week/FindSumPairs.java b/src/main/java/com/code/leet/week/FindSumPairs.java
new file mode 100644
index 0000000..2351f6e
--- /dev/null
+++ b/src/main/java/com/code/leet/week/FindSumPairs.java
@@ -0,0 +1,38 @@
+package com.code.leet.week;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+/**
+ * @Author: 轩辕龙儿
+ * @Date: 2021/5/16 11:03
+ * @Description:
+ */
+class FindSumPairs {
+
+    int[] nums1;
+    int[] nums2;
+    Map<Integer, Integer> map = new HashMap<>();
+
+    public FindSumPairs(int[] nums1, int[] nums2) {
+        this.nums1 = nums1;
+        this.nums2 = nums2;
+        for (int i = 0; i < nums2.length; i++) {
+            map.put(nums2[i], map.getOrDefault(nums2[i], 0) + 1);
+        }
+    }
+
+    public void add(int index, int val) {
+        map.put(nums2[index], map.getOrDefault(nums2[index], 0) - 1);
+        map.put(nums2[index] + val, map.getOrDefault(nums2[index] + val, 0) + 1);
+        nums2[index] += val;
+    }
+
+    public int count(int tot) {
+        int count = 0;
+        for (int i = 0; i < nums1.length; i++) {
+            count += map.getOrDefault(tot - nums1[i], 0);
+        }
+        return count;
+    }
+}
diff --git a/src/main/java/com/code/leet/week/Solution241.java b/src/main/java/com/code/leet/week/Solution241.java
new file mode 100644
index 0000000..95ca4f3
--- /dev/null
+++ b/src/main/java/com/code/leet/week/Solution241.java
@@ -0,0 +1,74 @@
+package com.code.leet.week;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * @Author: 轩辕龙儿
+ * @Date: 2021/5/16 10:30
+ * @Description:
+ */
+public class Solution241 {
+    public static void main(String[] args) {
+//        Solution241 solution = new Solution241();
+//        System.out.println(solution.minSwaps("1110"));
+//        FindSumPairs findSumPairs = new FindSumPairs(new int[]{1, 1, 2, 2, 2, 3},new int[]{1, 4, 5, 2, 5, 4});
+//        System.out.println(findSumPairs.count(7));
+//        findSumPairs.add(3,2);
+//        findSumPairs.count(8);
+//        findSumPairs.count(4);
+//        findSumPairs.add(0,1);
+//        findSumPairs.add(1,1);
+//        findSumPairs.count(7);
+        System.out.println(1^2);
+    }
+
+    public int subsetXORSum(int[] nums) {
+        if (nums.length == 0) {
+            return 0;
+        }
+        return getArr(nums, 0, new ArrayList<>(), 0);
+    }
+
+    private int getArr(int[] nums, int index, List<Integer> xors, int result) {
+        if (index == nums.length) {
+            return result;
+        }
+        List<Integer> temp = xors;
+        for (int xor : temp) {
+            result += xor ^ nums[index];
+        }
+        result += nums[index];
+        xors.add(nums[index]);
+        return getArr(nums, index + 1, xors, result);
+    }
+
+    public int minSwaps(String s) {
+        int s0 = s.replace("0", "").length();
+        int s1 = s.replace("1", "").length();
+        if (Math.abs(s0 - s1) > 1) {
+            return -1;
+        }
+        int com = 0;
+        int m0 = 0;
+        for (int i = 0; i < s.length(); i++) {
+            if (com != s.charAt(i) - '0') {
+                m0++;
+            }
+            com = 1 - com;
+        }
+        m0 = m0 % 2 == 0 ? m0 : Integer.MAX_VALUE;
+        com = 1;
+        int m1 = 0;
+        for (int i = 0; i < s.length(); i++) {
+            if (com != s.charAt(i) - '0') {
+                m1++;
+            }
+            com = 1 - com;
+        }
+        m1 = m1 % 2 == 0 ? m1 : Integer.MAX_VALUE;
+        return Math.min(m0, m1) / 2;
+    }
+}
+
+