346. 数据流中的移动平均值
给定一个整数数据流和一个窗口大小，根据该滑动窗口的大小，计算其所有整数的移动平均值。
实现 MovingAverage 类：
MovingAverage(int size) 用窗口大小 size 初始化对象。double next(int val) 计算并返回数据流中最后 size 个值的移动平均值。
示例：
输入： ["MovingAverage", "next", "next", "next", "next"] [[3], [1], [10], [3], [5]] 输出： [null, 1.0, 5.5, 4.66667, 6.0] 解释： MovingAverage movingAverage = new MovingAverage(3); movingAverage.next(1); // 返回 1.0 = 1 / 1 movingAverage.next(10); // 返回 5.5 = (1 + 10) / 2 movingAverage.next(3); // 返回 4.66667 = (1 + 10 + 3) / 3 movingAverage.next(5); // 返回 6.0 = (10 + 3 + 5) / 3
提示：
1 <= size <= 1000-105 <= val <= 105next 方法 104 次原站题解
javascript 解法, 执行用时: 96 ms, 内存消耗: 47.3 MB, 提交时间: 2023-10-15 18:38:09
/**
* @param {number} size
*/
var MovingAverage = function(size) {
this.queue = [];
this.size = size;
this.sum = 0;
};
/**
* @param {number} val
* @return {number}
*/
MovingAverage.prototype.next = function(val) {
if (this.queue.length === this.size) {
this.sum -= this.queue.shift();
}
this.queue.push(val);
this.sum += val;
return this.sum / this.queue.length;
};
/**
* Your MovingAverage object will be instantiated and called as such:
* var obj = new MovingAverage(size)
* var param_1 = obj.next(val)
*/
golang 解法, 执行用时: 16 ms, 内存消耗: 6.7 MB, 提交时间: 2023-10-15 18:37:38
type MovingAverage struct {
size, sum int
q []int
}
func Constructor(size int) MovingAverage {
return MovingAverage{size: size}
}
func (m *MovingAverage) Next(val int) float64 {
if len(m.q) == m.size {
m.sum -= m.q[0]
m.q = m.q[1:]
}
m.sum += val
m.q = append(m.q, val)
return float64(m.sum) / float64(len(m.q))
}
/**
* Your MovingAverage object will be instantiated and called as such:
* obj := Constructor(size);
* param_1 := obj.Next(val);
*/
java 解法, 执行用时: 37 ms, 内存消耗: 47 MB, 提交时间: 2023-10-15 18:37:21
class MovingAverage {
Queue<Integer> queue;
int size;
double sum;
public MovingAverage(int size) {
queue = new ArrayDeque<Integer>();
this.size = size;
sum = 0;
}
public double next(int val) {
if (queue.size() == size) {
sum -= queue.poll();
}
queue.offer(val);
sum += val;
return sum / queue.size();
}
}
/**
* Your MovingAverage object will be instantiated and called as such:
* MovingAverage obj = new MovingAverage(size);
* double param_1 = obj.next(val);
*/
cpp 解法, 执行用时: 20 ms, 内存消耗: 14 MB, 提交时间: 2023-10-15 18:37:05
class MovingAverage {
public:
MovingAverage(int size) {
this->size = size;
this->sum = 0.0;
}
double next(int val) {
if (qu.size() == size) {
sum -= qu.front();
qu.pop();
}
qu.emplace(val);
sum += val;
return sum / qu.size();
}
private:
int size;
double sum;
queue<int> qu;
};
/**
* Your MovingAverage object will be instantiated and called as such:
* MovingAverage* obj = new MovingAverage(size);
* double param_1 = obj->next(val);
*/
python3 解法, 执行用时: 68 ms, 内存消耗: 19.5 MB, 提交时间: 2023-10-15 18:36:51
class MovingAverage:
def __init__(self, size: int):
self.size = size
self.sum = 0
self.q = deque()
def next(self, val: int) -> float:
if len(self.q) == self.size:
self.sum -= self.q.popleft()
self.sum += val
self.q.append(val)
return self.sum / len(self.q)
# Your MovingAverage object will be instantiated and called as such:
# obj = MovingAverage(size)
# param_1 = obj.next(val)