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two-sum.ts
EASY

Two Sum

Given an array of integers, return the indices of the two numbers that add up to a specific target.

ArrayHash MapO(n)
function twoSum(nums, target) {
  const seen = new Map();
  for (let i = 0; i < nums.length; i++) {
    const need = target - nums[i];
    if (seen.has(need))
      return [seen.get(need), i];
    seen.set(nums[i], i);
  }
}
All 24 test cases passed · 41 ms
ArraysHash MapsTwo PointersBinary SearchLinked ListsRecursionTreesGraphsDPGreedyBacktrackingHeapsSortingBit TricksArraysHash MapsTwo PointersBinary SearchLinked ListsRecursionTreesGraphsDPGreedyBacktrackingHeapsSortingBit Tricks
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