diff --git a/OnlineJudges/lydsy/1022.cpp b/OnlineJudges/lydsy/1022.cpp
new file mode 100644
index 0000000..dc8539d
--- /dev/null
+++ b/OnlineJudges/lydsy/1022.cpp
@@ -0,0 +1,21 @@
+//http://wenku.baidu.com/link?url=hdO-izu3ggfWlLUkg9YTHcU28Z1TDzVHtXzDSDnDl4yVyTMjcA3i1qb9BNbJMVbSRm2q9D5MpN12DQNX_N1J4NJhb2larJdiw7-o8Ki9Hqa
+#include <cstdio>
+int main()
+{
+    int T, n, x;
+    scanf("%d", &T);
+    while (T--)
+    {
+        scanf("%d", &n);
+        int ans = 0, f = 1;
+        while (n--)
+        {
+            scanf("%d", &x);
+            ans ^= x;
+            if (x != 1) f = 0;
+        }
+        ans = ans ? 1 : 0;
+        puts(f ^ ans ? "John" : "Brother");
+    }
+    return 0;
+}
\ No newline at end of file
diff --git a/OnlineJudges/lydsy/2467.cpp b/OnlineJudges/lydsy/2467.cpp
new file mode 100644
index 0000000..3829836
--- /dev/null
+++ b/OnlineJudges/lydsy/2467.cpp
@@ -0,0 +1,22 @@
+//http://blog.csdn.net/popoqqq/article/details/41348131
+#include <cstdio>
+const int mod = 2007;
+int fast_pow(int base, int p)
+{
+    int ans = 1;
+    for (base %= mod; p; base = base * base % mod, p >>= 1)
+        if (p & 1)
+            ans = ans * base % mod;
+    return ans;
+}
+int main()
+{
+    int t, x;
+    scanf("%d", &t);
+    while (t--)
+    {
+        scanf("%d", &x);
+        printf("%d\n", 4 * x % mod * fast_pow(5, x - 1) % mod);
+    }
+    return 0;
+}
\ No newline at end of file
diff --git a/OnlineJudges/lydsy/3505.cpp b/OnlineJudges/lydsy/3505.cpp
new file mode 100644
index 0000000..1ebccd2
--- /dev/null
+++ b/OnlineJudges/lydsy/3505.cpp
@@ -0,0 +1,17 @@
+//http://blog.csdn.net/popoqqq/article/details/39779647
+#include <cstdio>
+int gcd(int x, int y) { return y == 0 ? x : gcd(y, x % y); }
+int main()
+{
+    int m, n;
+    scanf("%d%d", &m, &n);
+    m++, n++;
+    long long ans = m * n;
+    ans = ans * (ans - 1) * (ans - 2) / 6;
+    for (int i = 0; i <= m; i++)
+        for (int j = 0; j <= n; j++)
+            if (i || j)
+                ans -= (i && j ? 2ll : 1ll) * (gcd(i, j) - 1) * (m - i) * (n - j);
+    printf("%lld", ans);
+    return 0;
+}
\ No newline at end of file
diff --git a/OnlineJudges/lydsy/4001.cpp b/OnlineJudges/lydsy/4001.cpp
new file mode 100644
index 0000000..bbe500f
--- /dev/null
+++ b/OnlineJudges/lydsy/4001.cpp
@@ -0,0 +1,9 @@
+//http://blog.miskcoo.com/2015/04/bzoj-4001
+#include <cstdio>
+int main()
+{
+    int n;
+    scanf("%d", &n);
+    printf("%.9lf", 1.0 * n * (n + 1) / 2 / (n * 2 - 1));
+    return 0;
+}
\ No newline at end of file