Add group-anagrams solution in TypeScript

Author: Jeehay28

group-anagrams/Jeehay28.ts

@@ -0,0 +1,62 @@
+// Approach 2
+// Time Complexity: O(n * L), where n = number of strings in strs, L = maximum length of a string in strs
+// Space Complexity: O(n * L)
+
+function groupAnagrams(strs: string[]): string[][] {
+
+  let sorted: { [key: string]: string[] } = {}
+
+  for (const str of strs) {
+
+      const arr = Array.from({ length: 26 }, () => 0)
+
+      for (const ch of str) {
+          arr[ch.charCodeAt(0) - "a".charCodeAt(0)] += 1
+      }
+
+      // const key = arr.join(""); // This can lead to key collisions.
+      const key = arr.join("#"); // ✅
+
+      if (!sorted[key]) {
+          sorted[key] = []
+      }
+
+      sorted[key].push(str)
+  }
+
+  return Object.values(sorted);
+};
+
+
+// Approach 1
+// Time Complexity: O(n * LlogL), where n = number of strings, L = average length of the strings
+// Space Complexity: O(n * L)
+
+// function groupAnagrams(strs: string[]): string[][] {
+//   // input: an array of strings, strs
+//   // output: the anagrams
+
+//   // eat -> e, a, t -> a, e, t
+//   // tea -> t, e, a -> a, e, t
+//   // ate -> a, t, e -> a, e, t
+
+//   let map = new Map<string, string[]>();
+//   let result: string[][] = [];
+
+//   for (const str of strs) {
+//     const temp = str.split("").sort().join("");
+
+//     if (map.has(temp)) {
+//       map.set(temp, [...map.get(temp)!, str]);
+//     } else {
+//       map.set(temp, [str]);
+//     }
+//   }
+
+//   for (const el of map.values()) {
+//     result.push(el);
+//   }
+
+//   return result;
+// }
+