Create 1331-rank-transform-of-an-array.js

Author: everthis

1331-rank-transform-of-an-array.js

@@ -0,0 +1,18 @@
+/**
+ * @param {number[]} arr
+ * @return {number[]}
+ */
+const arrayRankTransform = function(arr) {
+  const hash = {}
+  for(let e of arr) {
+    hash[e] = 1
+  }
+  const keys = Object.keys(hash)
+  keys.sort((a, b) => a - b)
+  const rank = {}
+  for(let i = 0, n= keys.length; i < n; i++) {
+    rank[keys[i]] = i + 1
+  }
+  
+  return arr.map(e => rank[e])
+};