[sooooo-an] WEEK 01 solutions

contains-duplicate/sooooo-an.ts

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+function containsDuplicate(nums: number[]): boolean {
+  return new Set(nums).size !== nums.length;
+}
+/**
+ * runtime: 24ms / Beats 27.12%
+ * memory 74.42MB / Beats 55.98%
+ */

longest-consecutive-sequence/sooooo-an.ts

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+function longestConsecutive(nums: number[]): number {
+  if (!nums.length) return 0;
+
+  nums.sort((a, b) => a - b);
+  let longest = 1;
+  let currentStreak = 1;
+
+  for (let i = 1; i < nums.length; i++) {
+    if (nums[i] === nums[i - 1]) continue;
+    if (nums[i] === nums[i - 1] + 1) {
+      currentStreak++;
+    } else {
+      longest = Math.max(longest, currentStreak);
+      currentStreak = 1;
+    }
+  }
+
+  return Math.max(longest, currentStreak);
+}
+
+/**
+ * * Runtime: 37ms / 74.15%
+ * * Memory: 67.88MB / 93.54%
+ */

top-k-frequent-elements/sooooo-an.ts

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+function topKFrequent(nums: number[], k: number): number[] {
+  const frequentMap = new Map<number, number>();
+
+  for (const num of nums) {
+    frequentMap.set(num, (frequentMap.get(num) ?? 0) + 1);
+  }
+
+  const sorted = Array.from(frequentMap.entries()).sort((a, b) => b[1] - a[1]);
+
+  return sorted.slice(0, k).map(([key]) => Number(key));
+}
+
+/**
+ * Runtime 9ms / 78.90%
+ * Memory 60.130MB / 66.67%
+ */

two-sum/sooooo-an.ts

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+function twoSum(nums: number[], target: number): number[] {
+  const visited: { [key: string]: boolean } = {};
+  for (let i = 0; i < nums.length; i++) {
+    const complement = target - nums[i];
+    if (visited[complement]) {
+      const complementIdx = nums.indexOf(complement);
+      return [i, complementIdx];
+    }
+    visited[nums[i]] = true;
+  }
+  return [];
+}
+
+/**
+ * runtime: O(n)
+ * memory O(n)
+ */