Branches- Amal

lib/exercises.js

@@ -1,17 +1,49 @@
 // This method will return an array of arrays.
 // Each subarray will have strings which are anagrams of each other
-// Time Complexity: ?
-// Space Complexity: ?
+// Time Complexity: O(n * m)
+// Space Complexity: O(n)
 function grouped_anagrams(strings) {
-  throw new Error("Method hasn't been implemented yet!");
+  let h = {}
+
+  strings.forEach((word) => {
+    const orderedChars = word.split("").sort().join("")
+    if(h[orderedChars]){
+      h[orderedChars].push(word)
+    }else{
+      h[orderedChars] = [word]
+    }
+  })
+  return Object.values(h)
 }
 
 // This method will return the k most common elements
 // in the case of a tie it will select the first occuring element.
-// Time Complexity: ?
-// Space Complexity: ?
+// Time Complexity: O(n)
+// Space Complexity: O(n)
 function top_k_frequent_elements(list, k) {
-  throw new Error("Method hasn't been implemented yet!");
+  if (list.length == 0 ){
+    return []
+  }
+let listObj = {}
+let res= [];
+  list.forEach((num) =>{
+    if(listObj[num]){
+      listObj[num] += 1
+    }else {
+      listObj[num] = 1
+    }
+  })
+  const maxArray = Object.keys(listObj).sort((function(a, b) {
+    if(listObj[a] == listObj[b]){
+      return -1
+    }else{
+      return listObj[a] - listObj[b]
+    }
+  })).reverse() 
+  for( let i = 0; i < k; i++){
+    res.push(parseInt(maxArray[i]))
+  }
+  return res
 }
 
 
@@ -30,4 +62,4 @@ module.exports = {
   grouped_anagrams,
   top_k_frequent_elements,
   valid_sudoku
-};
+}

test/exercises.test.js

@@ -74,7 +74,7 @@ describe("exercises", function () {
     });
   });
 
-  describe.skip("top_k_frequent_elements", function () {
+  describe("top_k_frequent_elements", function () {
     it("works with example 1", function () {
       // Arrange
       const list = [1, 1, 1, 2, 2, 3];