3Sum Closest

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

class Solution {
public:
    int threeSumClosest(vector<int>& nums, int target) {
        int L = nums.size();
        if(L == 3)
        {
            return nums[0]+nums[1]+nums[2];
        }
        sort(nums.begin(),nums.end());
        int j,k,min = abs(target - (nums[0]+nums[1]+nums[L-1])),res = nums[0]+nums[1]+nums[2];
        for(int i = 0;i < L-1; i++ )
        {
            //初始化下标
            j = i+1;
            k = L-1;
            while(j < k)
            {
                int tmp = abs(target - (nums[i]+nums[j]+nums[k]));
                if(tmp < min)
                {
                    min = tmp;
                    res = nums[i]+nums[j]+nums[k];
                }
                if(nums[i]+nums[j]+nums[k] > target)
                {
                    --k;
                    continue;
                }
                else if(nums[i]+nums[j]+nums[k] < target)
                {
                    ++j;
                    continue;
                }
                else
                    return target;
            }
        }
        return res;
    }
};