diff --git a/LeetCode/933.number-of-recent-calls.cpp b/LeetCode/933.number-of-recent-calls.cpp
new file mode 100644
index 0000000..20c3f03
--- /dev/null
+++ b/LeetCode/933.number-of-recent-calls.cpp
@@ -0,0 +1,21 @@
+#include<deque>
+
+class RecentCounter {
+    deque<int> req;
+public:
+    RecentCounter() {
+        req = {};    
+    }
+    
+    int ping(int t) {
+        req.push_back(t);
+        while(req.front() < t-3000) req.pop_front();
+        return req.size();
+    }
+};
+
+/**
+ * Your RecentCounter object will be instantiated and called as such:
+ * RecentCounter* obj = new RecentCounter();
+ * int param_1 = obj->ping(t);
+ */