LeetCode – Refresh – 3sumclosest

This problem is almost like 3sum. Actually it needs the same skip steps for j and k. But LeetCode did not put the test case there. So just put like this.

class Solution {
public:
    int threeSumClosest(vector<int> &num, int target) {
        int len = num.size(), result = num[0] + num[1] + num[2], i = 0, j = 0, k = 0;
        sort(num.begin(), num.end());
        for (i = 0; i < len-2; i++) {
            if (i > 0 && num[i] == num[i-1]) continue;
            j = i+1, k = len-1;
            while (j < k) {
                int sum = num[i] + num[j] + num[k];
                if (fabs(sum - target) < fabs(result - target)) result = sum;
                if (sum > target) k--;
                else j++;
            }
        }
        return result;
    }
};