Create 981-time-based-key-value-store.js

Author: everthis

981-time-based-key-value-store.js

@@ -0,0 +1,47 @@
+/**
+ * Initialize your data structure here.
+ */
+const TimeMap = function() {
+   this.hash = {}
+};
+
+/** 
+ * @param {string} key 
+ * @param {string} value 
+ * @param {number} timestamp
+ * @return {void}
+ */
+TimeMap.prototype.set = function(key, value, timestamp) {
+  if(this.hash[key] == null) this.hash[key] = []
+  this.hash[key].push([value, timestamp])
+};
+
+/** 
+ * @param {string} key 
+ * @param {number} timestamp
+ * @return {string}
+ */
+TimeMap.prototype.get = function(key, timestamp) {
+  if(this.hash[key] == null) return ''
+  const arr = this.hash[key]
+
+  let l = 0, r = arr.length
+  while(l < r) {
+    const mid = l + ((r - l) >> 1)
+    if(arr[mid][1] <= timestamp) {
+      l = mid + 1
+    } else {
+      r = mid
+    }
+  }
+
+  if(r === 0) return ''
+  return arr[r - 1][0]
+};
+
+/** 
+ * Your TimeMap object will be instantiated and called as such:
+ * var obj = new TimeMap()
+ * obj.set(key,value,timestamp)
+ * var param_2 = obj.get(key,timestamp)
+ */