Update 1146-snapshot-array.js

Author: everthis

1146-snapshot-array.js

@@ -1,3 +1,59 @@
+/**
+ * @param {number} length
+ */
+const SnapshotArray = function(length) {
+  this.snaps = Array(length)
+  this.snapId = 0
+};
+
+/** 
+ * @param {number} index 
+ * @param {number} val
+ * @return {void}
+ */
+SnapshotArray.prototype.set = function(index, val) {
+  if(this.snaps[index] == null) {
+    this.snaps[index] = {}
+  }
+  this.snaps[index][this.snapId] = val
+};
+
+/**
+ * @return {number}
+ */
+SnapshotArray.prototype.snap = function() {
+  return this.snapId++
+};
+
+/** 
+ * @param {number} index 
+ * @param {number} snap_id
+ * @return {number}
+ */
+SnapshotArray.prototype.get = function(index, snap_id) {
+  let res = 0
+  let id = snap_id
+  while(id >= 0) {
+    if(this.snaps[index] == null || this.snaps[index][id] == null) id--
+    else {
+      res = this.snaps[index][id]
+      break
+    }
+  }
+  
+  return res
+};
+
+/** 
+ * Your SnapshotArray object will be instantiated and called as such:
+ * var obj = new SnapshotArray(length)
+ * obj.set(index,val)
+ * var param_2 = obj.snap()
+ * var param_3 = obj.get(index,snap_id)
+ */
+
+// another
+
 /**
  * @param {number[]} nums
  * @param {number} target