<p>Given an integer array <code>nums</code> of length <code>n</code> and an integer <code>target</code>, find three integers in <code>nums</code> such that the sum is closest to <code>target</code>.</p>

<p>Return <em>the sum of the three integers</em>.</p>

<p>You may assume that each input would have exactly one solution.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [-1,2,1,-4], target = 1
<strong>Output:</strong> 2
<strong>Explanation:</strong> The sum that is closest to the target is 2. (-1 + 2 + 1 = 2).
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [0,0,0], target = 1
<strong>Output:</strong> 0
<strong>Explanation:</strong> The sum that is closest to the target is 0. (0 + 0 + 0 = 0).
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>3 &lt;= nums.length &lt;= 500</code></li>
	<li><code>-1000 &lt;= nums[i] &lt;= 1000</code></li>
	<li><code>-10<sup>4</sup> &lt;= target &lt;= 10<sup>4</sup></code></li>
</ul>

class Solution {
public:
    int threeSumClosest(vector<int>& nums, int target) {
        ranges::sort(nums);
        auto best = nums[0] + nums[1] + nums[2];

        for (int i = 0; i < nums.size()-1; i++) {
            int left = i+1;
            int right = nums.size() - 1;
            while (left < right) {
                auto const cur = nums[i] + nums[left] + nums[right];
                if (std::abs(target-best) > std::abs(target-cur)) {
                    best = cur; 
                }
                if (cur < target) {
                    left++;
                } else if (cur > target) {
                    right--;
                } else {
                    return target;
                }
            }
        }
        return best;
    }
};
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