Number of Recent Calls

Similar Problems:

Write a class RecentCounter to count recent requests.

It has only one method: ping(int t), where t represents some time in milliseconds.

Return the number of pings that have been made from 3000 milliseconds ago until now.

Any ping with time in [t – 3000, t] will count, including the current ping.

It is guaranteed that every call to ping uses a strictly larger value of t than before.

Example 1:

Input: inputs = ["RecentCounter","ping","ping","ping","ping"], inputs = [[],[1],[100],[3001],[3002]] Output: [null,1,2,3,3]

Note:

- Each test case will have at most 10000 calls to ping.
- Each test case will call ping with strictly increasing values of t.
- Each call to ping will have 1 <= t <= 10^9.

Github: code.dennyzhang.com

Credits To: leetcode.com

Leave me comments, if you have better ways to solve.

- Solution: queue with array

// https://code.dennyzhang.com/number-of-recent-calls // Basic Ideas: queue // // Complexity: Time O(n), Space O(n) type RecentCounter struct { l []int } func Constructor() RecentCounter { return RecentCounter{[]int{}} } func (this *RecentCounter) Ping(t int) int { this.l = append(this.l, t) i, t2 := 0, t - 3000 for ; i<len(this.l); i++ { if this.l[i] >= t2 { break } } this.l = this.l[i:] return len(this.l) } /** * Your RecentCounter object will be instantiated and called as such: * obj := Constructor(); * param_1 := obj.Ping(t); */