diff --git a/QOJ/6128.cpp b/QOJ/6128.cpp
new file mode 100644
index 0000000..ea8e444
--- /dev/null
+++ b/QOJ/6128.cpp
@@ -0,0 +1,48 @@
+/**
+ * @file 6128.cpp
+ * @author Macesuted (i@macesuted.moe)
+ * @date 2024-10-18
+ *
+ * @copyright Copyright (c) 2024
+ *
+ */
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#define endl '\n'
+
+#define maxn 1000005
+
+int a[maxn];
+
+void solve(void) {
+    int n;
+    cin >> n;
+    string s, t;
+    cin >> s >> t;
+    for (int i = 1; i <= n; i++) a[i] = (s[i - 1] ^ t[i - 1]);
+    a[n + 1] = 0;
+    for (int i = n + 1; i; i--) a[i] ^= a[i - 1];
+    int cnt = 0;
+    for (int i = 1; i <= n + 1; i++) cnt += a[i];
+    if (cnt == 0)
+        cout << (int64_t)n * (n + 1) / 2 << endl;
+    else if (cnt == 2)
+        cout << 2 * (n - 1) << endl;
+    else if (cnt == 4)
+        cout << 6 << endl;
+    else
+        cout << 0 << endl;
+    return;
+}
+
+int main() {
+    ios::sync_with_stdio(false), cin.tie(nullptr);
+
+    int _ = 1;
+    cin >> _;
+    while (_--) solve();
+
+    return 0;
+}
\ No newline at end of file
diff --git a/QOJ/6129.cpp b/QOJ/6129.cpp
new file mode 100644
index 0000000..dbdaaa7
--- /dev/null
+++ b/QOJ/6129.cpp
@@ -0,0 +1,77 @@
+/**
+ * @file 6129.cpp
+ * @author Macesuted (i@macesuted.moe)
+ * @date 2024-10-18
+ *
+ * @copyright Copyright (c) 2024
+ *
+ */
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#define endl '\n'
+
+#define maxn 200005
+
+int s[maxn], a[maxn], b[maxn];
+
+void solve(void) {
+    int n, m;
+    cin >> n >> m;
+    string sss;
+    cin >> sss;
+    int len = sss.size();
+    for (int i = 1; i <= len; i++) s[i] = sss[i - 1] - '0';
+    for (a[1] = 1; a[1] <= 9; a[1]++) {
+        bool chk = true;
+        int p = 1;
+        for (int j = 1; j <= m && chk; j++)
+            if (p <= len && s[p] % a[1] == 0)
+                b[j] = s[p] / a[1], p++;
+            else if (p + 1 <= len && (s[p] * 10 + s[p + 1]) % a[1] == 0 && (s[p] * 10 + s[p + 1]) / a[1] < 10)
+                b[j] = (s[p] * 10 + s[p + 1]) / a[1], p += 2;
+            else
+                chk = false;
+        if (!chk) continue;
+        for (int i = 2; i <= n && chk; i++) {
+            a[i] = -1;
+            for (int j = 1; j <= m && chk; j++) {
+                if (!b[j]) {
+                    if (p <= len && s[p] == 0)
+                        p++;
+                    else
+                        chk = false;
+                    continue;
+                }
+                int v = -1;
+                if (p <= len && s[p] % b[j] == 0)
+                    v = s[p] / b[j], p++;
+                else if (p + 1 <= len && (s[p] * 10 + s[p + 1]) % b[j] == 0 && (s[p] * 10 + s[p + 1]) / b[j] < 10)
+                    v = (s[p] * 10 + s[p + 1]) / b[j], p += 2;
+                else
+                    chk = false;
+                if (a[i] == -1) a[i] = v;
+                if (a[i] != v) chk = false;
+            }
+        }
+        if (!chk || p != len + 1) continue;
+        for (int i = 1; i <= n; i++) cout << a[i];
+        cout << ' ';
+        for (int i = 1; i <= m; i++) cout << b[i];
+        cout << endl;
+        return;
+    }
+    cout << "Impossible" << endl;
+    return;
+}
+
+int main() {
+    ios::sync_with_stdio(false), cin.tie(nullptr);
+
+    int _ = 1;
+    cin >> _;
+    while (_--) solve();
+
+    return 0;
+}
\ No newline at end of file
diff --git a/QOJ/6130.cpp b/QOJ/6130.cpp
new file mode 100644
index 0000000..62ddb48
--- /dev/null
+++ b/QOJ/6130.cpp
@@ -0,0 +1,52 @@
+/**
+ * @file 6130.cpp
+ * @author Macesuted (i@macesuted.moe)
+ * @date 2024-10-18
+ *
+ * @copyright Copyright (c) 2024
+ *
+ */
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#define endl '\n'
+
+#define maxn 100005
+
+int64_t a[maxn], c[maxn];
+int n;
+int64_t m;
+
+bool check(int64_t lim) {
+    for (int i = 1; i <= n; i++) c[i] = (lim - 1) / a[i] + 1;
+    int64_t rest = m;
+    for (int i = 1; i < n && rest >= 0; i++) {
+        c[i]--, rest--;
+        if (c[i] > 0) c[i + 1] -= c[i], rest -= 2 * c[i], c[i] = 0;
+    }
+    if (c[n] > 0) rest -= 2 * c[n] - 1;
+    return rest >= 0;
+}
+
+void solve(void) {
+    cin >> n >> m;
+    for (int i = 1; i <= n; i++) cin >> a[i];
+    int64_t l = 0, r = 1e18;
+    while (l + 1 < r) {
+        int64_t mid = (l + r) >> 1;
+        (check(mid) ? l : r) = mid;
+    }
+    cout << l << endl;
+    return;
+}
+
+int main() {
+    ios::sync_with_stdio(false), cin.tie(nullptr);
+
+    int _ = 1;
+    cin >> _;
+    while (_--) solve();
+
+    return 0;
+}
\ No newline at end of file
diff --git a/QOJ/6131.cpp b/QOJ/6131.cpp
new file mode 100644
index 0000000..8ac7d98
--- /dev/null
+++ b/QOJ/6131.cpp
@@ -0,0 +1,42 @@
+/**
+ * @file 6131.cpp
+ * @author Macesuted (i@macesuted.moe)
+ * @date 2024-10-18
+ *
+ * @copyright Copyright (c) 2024
+ *
+ */
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#define endl '\n'
+
+#define maxn 1005
+
+void solve(void) {
+    int n, k;
+    cin >> n >> k;
+    vector<int> ans;
+    for (int v = 1; v < n && k; v++) {
+        bool chk = true;
+        for (int i = 0; i < n && chk; i++) chk &= ((i ^ v) < n);
+        if (chk) k--, ans.push_back(v);
+    }
+    if (k) return cout << "Impossible" << endl, void();
+    for (auto i : ans) {
+        for (int j = 0; j < n; j++) cout << (i ^ j) + 1 << ' ';
+        cout << endl;
+    }
+    return;
+}
+
+int main() {
+    ios::sync_with_stdio(false), cin.tie(nullptr);
+
+    int _ = 1;
+    cin >> _;
+    while (_--) solve();
+
+    return 0;
+}
\ No newline at end of file
diff --git a/QOJ/6138.cpp b/QOJ/6138.cpp
new file mode 100644
index 0000000..f17232b
--- /dev/null
+++ b/QOJ/6138.cpp
@@ -0,0 +1,43 @@
+/**
+ * @file 6138.cpp
+ * @author Macesuted (i@macesuted.moe)
+ * @date 2024-10-18
+ *
+ * @copyright Copyright (c) 2024
+ *
+ */
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#define endl '\n'
+
+void solve(void) {
+    int x, k;
+    cin >> x >> k;
+    while (x >= 2 && k) {
+        int v = x, sum = 0;
+        while (v) {
+            int t = v % 10;
+            v /= 10;
+            if (t == 8)
+                sum += 2;
+            else if (t == 0 || t == 4 || t == 6 || t == 9)
+                sum++;
+        }
+        x = sum, k--;
+    }
+    if (k) x ^= k & 1;
+    cout << x << endl;
+    return;
+}
+
+int main() {
+    ios::sync_with_stdio(false), cin.tie(nullptr);
+
+    int _ = 1;
+    cin >> _;
+    while (_--) solve();
+
+    return 0;
+}
\ No newline at end of file