Design Hit Counter

Description

null

Solution(javascript)

// /**
//  * Initialize your data structure here.
//  */
// const HitCounter = function () {
//   this.map = {}
// }

// /**
//  * Record a hit.
//         @param timestamp - The current timestamp (in seconds granularity).
//  * @param {number} timestamp
//  * @return {void}
//  */
// HitCounter.prototype.hit = function (timestamp) {
//   this.map[timestamp] = (this.map[timestamp] || 0) + 1
// }

// /**
//  * Return the number of hits in the past 5 minutes.
//         @param timestamp - The current timestamp (in seconds granularity).
//  * @param {number} timestamp
//  * @return {number}
//  */
// HitCounter.prototype.getHits = function (timestamp) {
//   let count = 0
//   for (let i = timestamp; i > timestamp - 300; i--) {
//     if (this.map[i] >= 1) {
//       count += this.map[i]
//     }
//   }
//   return count
// }


/**
 * Initialize your data structure here.
 */
const HitCounter = function () {
  this.indices = []
  this.counts = []
}

/**
 * Record a hit.
        @param timestamp - The current timestamp (in seconds granularity).
 * @param {number} timestamp
 * @return {void}
 */
HitCounter.prototype.hit = function (timestamp) {
  const index = timestamp % 300
  if (timestamp !== this.indices[index]) {
    this.indices[index] = timestamp
    this.counts[index] = 1
  } else {
    this.counts[index] += 1
  }
}

/**
 * Return the number of hits in the past 5 minutes.
        @param timestamp - The current timestamp (in seconds granularity).
 * @param {number} timestamp
 * @return {number}
 */
HitCounter.prototype.getHits = function (timestamp) {
  let count = 0
  for (let i = 0; i < 300; i++) {
    if (timestamp - this.indices[i] < 300) {
      count += this.counts[i]
    }
  }
  return count
}