cpp: add “933. Number of Recent Calls”

Signed-off-by: Matej Focko <me@mfocko.xyz>

cpp/number-of-recent-calls.cpp

@@ -0,0 +1,39 @@
+#include <cassert>
+#include <queue>
+
+class RecentCounter {
+    std::queue<int> calls;
+
+  public:
+    RecentCounter() {}
+
+    int ping(int t) {
+        calls.push(t);
+
+        while (calls.front() < t - 3000) {
+            calls.pop();
+        }
+
+        return static_cast<int>(calls.size());
+    }
+};
+
+/**
+ * Your RecentCounter object will be instantiated and called as such:
+ * RecentCounter* obj = new RecentCounter();
+ * int param_1 = obj->ping(t);
+ */
+
+static void test_1() {
+    RecentCounter c;
+
+    assert(c.ping(1) == 1);
+    assert(c.ping(100) == 2);
+    assert(c.ping(3001) == 3);
+    assert(c.ping(3002) == 3);
+}
+
+int main() {
+    test_1();
+    return 0;
+}