Create 659-split-array-into-consecutive-subsequences.js

Author: everthis

659-split-array-into-consecutive-subsequences.js

@@ -0,0 +1,28 @@
+/**
+ * @param {number[]} nums
+ * @return {boolean}
+ */
+const isPossible = function(nums) {
+  const freq = new Map()
+  const build = new Map()
+  for (let el of nums) {
+    freq.has(el) ? freq.set(el, freq.get(el) + 1) : freq.set(el, 1)
+  }
+  for (let item of nums) {
+    if (freq.get(item) === 0) continue
+    else if (getOrDefault(build, item) > 0) {
+      build.set(item, build.get(item) - 1)
+      build.set(item + 1, getOrDefault(build, item + 1) + 1)
+    } else if (getOrDefault(freq, item + 1) > 0 && getOrDefault(freq, item + 2) > 0) {
+      freq.set(item + 1, freq.get(item + 1) - 1)
+      freq.set(item + 2, freq.get(item + 2) - 1)
+      build.set(item + 3, getOrDefault(build, item + 3) + 1)
+    } else return false
+    freq.set(item, freq.get(item) - 1)
+  }
+  return true
+}
+
+function getOrDefault(map, key) {
+  return map.get(key) || 0
+}