add new solutions

solutions/9/q933/solution.go

@@ -0,0 +1,46 @@
+package q933
+
+type RecentCounter struct{ reqs []int }
+
+func Constructor() RecentCounter {
+	return RecentCounter{reqs: make([]int, 0, 1024)}
+}
+
+func (c *RecentCounter) Ping(t int) int {
+	if cap(c.reqs) == len(c.reqs) {
+		alloc := make([]int, max(2048, 2*len(c.reqs)))
+		copy(alloc, c.reqs)
+		c.reqs = alloc[:len(c.reqs)]
+	}
+
+	c.reqs = append(c.reqs, t)
+
+	// Fast path
+	if len(c.reqs) < 8 || c.reqs[7] >= t-3000 {
+		i := 0
+		for c.reqs[i] < t-3000 {
+			i++
+		}
+		c.reqs = c.reqs[i:]
+		return len(c.reqs)
+	}
+
+	// Use binary search to find the cut position
+	l, r := 0, len(c.reqs)
+	for l < r {
+		m := (l + r) / 2
+		if c.reqs[m] < t-3000 {
+			l = m + 1
+		} else {
+			r = m
+		}
+	}
+	c.reqs = c.reqs[l:]
+	return len(c.reqs)
+}
+
+/**
+ * Your RecentCounter object will be instantiated and called as such:
+ * obj := Constructor();
+ * param_1 := obj.Ping(t);
+ */