README.md

359. 日志速率限制器

English Version

题目描述

请你设计一个日志系统，可以流式接收消息以及它的时间戳。每条 不重复 的消息最多只能每 10 秒打印一次。也就是说，如果在时间戳 t 打印某条消息，那么相同内容的消息直到时间戳变为 t + 10 之前都不会被打印。

所有消息都按时间顺序发送。多条消息可能到达同一时间戳。

实现 Logger 类：

• Logger() 初始化 logger 对象
• bool shouldPrintMessage(int timestamp, string message) 如果这条消息 message 在给定的时间戳 timestamp 应该被打印出来，则返回 true ，否则请返回 false 。

 

示例：

输入：
["Logger", "shouldPrintMessage", "shouldPrintMessage", "shouldPrintMessage", "shouldPrintMessage", "shouldPrintMessage", "shouldPrintMessage"]
[[], [1, "foo"], [2, "bar"], [3, "foo"], [8, "bar"], [10, "foo"], [11, "foo"]]
输出：
[null, true, true, false, false, false, true]

解释：
Logger logger = new Logger();
logger.shouldPrintMessage(1, "foo");  // 返回 true ，下一次 "foo" 可以打印的时间戳是 1 + 10 = 11
logger.shouldPrintMessage(2, "bar");  // 返回 true ，下一次 "bar" 可以打印的时间戳是 2 + 10 = 12
logger.shouldPrintMessage(3, "foo");  // 3 < 11 ，返回 false
logger.shouldPrintMessage(8, "bar");  // 8 < 12 ，返回 false
logger.shouldPrintMessage(10, "foo"); // 10 < 11 ，返回 false
logger.shouldPrintMessage(11, "foo"); // 11 >= 11 ，返回 true ，下一次 "foo" 可以打印的时间戳是 11 + 10 = 21

 

提示：

• 0 <= timestamp <= 109
• 每个 timestamp 都将按非递减顺序（时间顺序）传递
• 1 <= message.length <= 30
• 最多调用 104 次 shouldPrintMessage 方法

解法

哈希表实现。

Python3

class Logger:

    def __init__(self):
        """
        Initialize your data structure here.
        """
        self.limiter = {}

    def shouldPrintMessage(self, timestamp: int, message: str) -> bool:
        """
        Returns true if the message should be printed in the given timestamp, otherwise returns false.
        If this method returns false, the message will not be printed.
        The timestamp is in seconds granularity.
        """
        t = self.limiter.get(message, 0)
        if t > timestamp:
            return False
        self.limiter[message] = timestamp + 10
        return True


# Your Logger object will be instantiated and called as such:
# obj = Logger()
# param_1 = obj.shouldPrintMessage(timestamp,message)

Java

class Logger {

    private Map<String, Integer> limiter;

    /** Initialize your data structure here. */
    public Logger() {
        limiter = new HashMap<>();
    }

    /** Returns true if the message should be printed in the given timestamp, otherwise returns false.
        If this method returns false, the message will not be printed.
        The timestamp is in seconds granularity. */
    public boolean shouldPrintMessage(int timestamp, String message) {
        int t = limiter.getOrDefault(message, 0);
        if (t > timestamp) {
            return false;
        }
        limiter.put(message, timestamp + 10);
        return true;
    }
}

/**
 * Your Logger object will be instantiated and called as such:
 * Logger obj = new Logger();
 * boolean param_1 = obj.shouldPrintMessage(timestamp,message);
 */

JavaScript

/**
 * Initialize your data structure here.
 */
var Logger = function () {
  this.limiter = {};
};

/**
 * Returns true if the message should be printed in the given timestamp, otherwise returns false.
        If this method returns false, the message will not be printed.
        The timestamp is in seconds granularity. 
 * @param {number} timestamp 
 * @param {string} message
 * @return {boolean}
 */
Logger.prototype.shouldPrintMessage = function (timestamp, message) {
  const t = this.limiter[message] || 0;
  if (t > timestamp) {
    return false;
  }
  this.limiter[message] = timestamp + 10;
  return true;
};

/**
 * Your Logger object will be instantiated and called as such:
 * var obj = new Logger()
 * var param_1 = obj.shouldPrintMessage(timestamp,message)
 */

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