diff --git a/src/a.out b/src/a.out
deleted file mode 100755
index 8553840..0000000
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diff --git a/src/chunyou b/src/chunyou
deleted file mode 100755
index 32869c5..0000000
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diff --git a/src/dikaer_tree.cpp b/src/dikaer_tree.cpp
new file mode 100644
index 0000000..442e05a
--- /dev/null
+++ b/src/dikaer_tree.cpp
@@ -0,0 +1,40 @@
+#include <cmath>
+#include <iostream>
+
+const int SIZE = 100 + 5;
+int n, a[SIZE], maxDeep, num;
+
+void solve(int left, int right, int deep) {
+    int i, j, min;
+    if (deep > maxDeep) {
+        maxDeep = deep;
+        num = 1;
+    } else if (deep == maxDeep) {
+        num++;
+    }
+    min = INFINITY;
+    for (i = left; i <= right; i++) {
+        if (min > a[i]) {
+            min = a[i];
+            j = i;
+        }
+    }
+    if (left < j) {
+        solve(left, j - 1, deep + 1);
+    }
+    if (j < right) {
+        solve(j, right, deep + 1);
+    }
+}
+
+int main() {
+    int i;
+    std::cin >> n;
+    for (i = 1; i <= n; i++) {
+        std::cin >> a[i];
+    }
+    maxDeep = 0;
+    solve(1, n, 1);
+    std::cout << maxDeep << " " << num << std::endl;
+    return 0;
+}
diff --git a/src/noip2011_program.cpp b/src/noip2011_program.cpp
new file mode 100644
index 0000000..5f8b595
--- /dev/null
+++ b/src/noip2011_program.cpp
@@ -0,0 +1,43 @@
+#include <iostream>
+
+const int V = 100;
+int n, m, ans, e[V][V];
+bool visited[V];
+
+void dfs(int x, int len) {
+    int i;
+    visited[x] = true;
+    if (len > ans) {
+        ans = len;
+    }
+    for (i = 1; i <= n; i++) {
+        if ((!visited[i]) && (e[x][i] != -1)) {
+            dfs(i, len + e[x][i]);
+        }
+    }
+    visited[x] = false;
+}
+
+int main() {
+    int i, j, a, b, c;
+    std::cin >> n >> m;
+    for (i = 1; i <= n; i++) {
+        for (j = 1; j <= m; j++) {
+            e[i][j] = -1;
+        }
+    }
+    for (i = 1; i <= m; i++) {
+        std::cin >> a >> b >> c;
+        e[a][b] = c;
+        e[b][a] = c;
+    }
+    for (i = 1; i <= n; i++) {
+        visited[i] = false;
+    }
+    ans = 0;
+    for (i = 1; i <= n; i++) {
+        dfs(i, 0);
+    }
+    std::cout << ans << std::endl;
+    return 0;
+}
diff --git a/src/noip2013_binary_search_tree.cpp b/src/noip2013_binary_search_tree.cpp
new file mode 100644
index 0000000..26205b5
--- /dev/null
+++ b/src/noip2013_binary_search_tree.cpp
@@ -0,0 +1,31 @@
+#include <cmath>
+#include <iostream>
+
+const int SIZE = 100;
+struct node {
+    int left_child, right_child, value;
+} a[SIZE];
+
+int is_bst(int root, int lower_bound, int upper_bound) {
+    int cur;
+    if (root == 0) {
+        return 1;
+    }
+    cur = a[root].value;
+    if ((cur > lower_bound) && (cur < upper_bound) &&
+        (is_bst(a[root].left_child, lower_bound, cur) == 1) &&
+        (is_bst(a[root].right_child, cur + 1, upper_bound) == 1)) {
+        return 1;
+    }
+    return 0;
+}
+
+int main() {
+    int i, n;
+    std::cin >> n;
+    for (i = 1; i <= n; i++) {
+        std::cin >> a[i].value >> a[i].left_child >> a[i].right_child;
+    }
+    std::cout << is_bst(1, -INFINITY, INFINITY) << std::endl;
+    return 0;
+}
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diff --git a/src/tudeoulalu b/src/tudeoulalu
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