Leetcode16--3sum Closest

Given an array S of n integers, find three integers in S such, the sum was closest to a Given number, target. Return the sum of the three integers. You may assume this each input would has exactly one solution.

For example, given array S = {-1 2 1 -4}, and target = 1.The sum that is closest to the target is 2. (-1 + 2 + 1 = 2).

Difficulty factor: Medium

Realize:

int threeSumClosest(vector<int> &num, int target) {    std::sort(num.begin(), num.end());    int closestVal = INT_MAX;    int closestSum = 0;    int small, big;    for (int i = 0; i < num.size() - 2; ++i){        small = i+1;        big = num.size()-1;        while (small < big) {            int sum = num[small] + num[big] + num[i];            int absVal = abs(sum - target);            if (absVal < closestVal) {                closestVal = absVal;                closestSum = sum;                cout << closestSum << endl;            }            if (sum > target) {                big--;            } else {                small++;            }        }    }    return closestSum;}

Leetcode16--3sum Closest