diff --git a/.gitignore b/.gitignore
index 05685e9..85625c7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,4 +3,5 @@
 !.gitignore
 !README.md
 !*.md
+!clean.sh
 tmp.md
\ No newline at end of file
diff --git a/P1020.cpp b/P1020.cpp
new file mode 100644
index 0000000..35888c0
--- /dev/null
+++ b/P1020.cpp
@@ -0,0 +1,48 @@
+#include <bits/stdc++.h>
+using namespace std;
+const int MAXN = 1e5 + 3;
+int n, t, a[MAXN], f[MAXN];
+int main()
+{
+    freopen("test.in", "r", stdin);
+    while (~scanf("%d", &a[++n]))
+        ;
+    --n;
+    f[0] = INT_MAX;
+    for (int i = 1; i <= n; ++i)
+    {
+        int l = 0, r = t + 1;
+        while (r - l > 1)
+        {
+            int m = l + (r - l) / 2;
+            if (f[m] >= a[i])
+                l = m;
+            else
+                r = m;
+        }
+        int x = l + 1;
+        if (x > t)
+            t = x;
+        f[x] = a[i];
+    }
+    printf("%d\n", t);
+    t = 0, memset(f, 0, sizeof(f)), f[0] = 0;
+    for (int i = 1; i <= n; ++i)
+    {
+        int l = 0, r = t + 1;
+        while (r - l > 1)
+        {
+            int m = l + (r - l) / 2;
+            if (f[m] < a[i])
+                l = m;
+            else
+                r = m;
+        }
+        int x = l + 1;
+        if (x > t)
+            t = x;
+        f[x] = a[i];
+    }
+    printf("%d\n", t);
+    return 0;
+}
diff --git a/clean.sh b/clean.sh
new file mode 100755
index 0000000..54e592f
--- /dev/null
+++ b/clean.sh
@@ -0,0 +1,2 @@
+find . -maxdepth 1 -type f ! -name "*.*" -executable -delete
+rm -rf *.in *.out
\ No newline at end of file