twosum.js.js

function twoSum(nums, target) {
  let numObj = {};
  for (let i = 0; i < nums.length; i++) {
    let complement = target - nums[i];
    if (numObj[complement] !== undefined) {
      return [numObj[complement], i];
    }
    numObj[nums[i]] = i;
  }
}



let target = 12;
let nums = [1, 4, 7, 9, 2, 4, 5, 6, 7, 5, 6]

console.log(twoSum(nums, target));