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Find indices in an array of the pair which totals up to target value in Javascript

Two Sum in Javascript

Find indices in an array of the pair which totals up to target value in Javascript.
const twoSum = (nums, target) => {
  let hash = {}
  for(i=0;i<nums.length;i++) {
    if (hash[nums[i]]!==undefined) {
      return [hash[nums[i]], i];
    }
    hash[target-nums[i]] = i;
  }
};

console.log(twoSum([2,7,11,15], 9)); // example

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