/**
 * @param {number[]} nums
 * @param {number} target
 * @return {number}
 */
var threeSumClosest = function (nums, target) {
  nums.sort(function (a, b) {
    return a - b;
  });
  var result = nums[0] + nums[1] + nums[2];
  var sum = Math.abs(result - target);
  var length = nums.length;
  for (var i = 0; i < length - 2; i++) {
    var leftPtr = i + 1;
    var rightPtr = length - 1;
    while (leftPtr < rightPtr) {
      var current = nums[i] + nums[leftPtr] + nums[rightPtr];
      if (Math.abs(current - target) < sum) {
        sum = Math.abs(current - target);
        result = current;
      } else {
        if (current > target) {
          rightPtr--;
        } else {
          leftPtr++;
        }
      }
    }
  }
  return result;
};