diff --git a/contests/Cadernaveis/BALE11.cpp b/contests/Cadernaveis/BALE11.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..16e26aaac348d50de8f24467b5ba5eb44c4c34c7
--- /dev/null
+++ b/contests/Cadernaveis/BALE11.cpp
@@ -0,0 +1,54 @@
+#include <bits/stdc++.h>
+
+#define MAX 101010
+#define MOD 1000000007
+#define inf 0x3f3f3f3f
+
+#define fi first
+#define se second
+#define sz size()
+#define pb push_back
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+
+using namespace std;
+
+typedef long long ll;
+typedef pair<int,int> ii;
+
+int v[MAX];
+int tree[MAX];
+
+int query(int idx) {
+  int sum = 0;
+  for (; idx > 0; idx -= (idx & -idx))
+    sum += tree[idx];
+
+  return sum;
+}
+
+
+void update(int idx, int val) {
+  for (; idx <= MAX; idx += (idx & -idx))
+    tree[idx] += val;
+}
+
+
+int main() {
+  ios::sync_with_stdio(0);
+  cin.tie(0);
+
+  int n;
+  cin >> n;
+  for (int i = 0; i < n; ++i)
+    cin >> v[i];
+
+  int ans = 0;
+  for (int i = 0; i < n; ++i) {
+    ans += query(n - v[i] + 1);
+    update(n - v[i] + 1, 1);
+  }
+
+  cout << ans << '\n';
+  return 0;
+}