16. 3Sum Closest

    /*
     * 16. 3Sum Closest
     * 2016-4-15 by Mingyang
     * 这道题目跟3sum几乎一样
     */
    public int threeSumClosest(int[] nums, int target) {
        int len=nums.length;
        if(len<3||nums==null)
          return 0;
          int res=0;
          int min=Integer.MAX_VALUE;
          Arrays.sort(nums);
        for(int i=0;i<len;i++){
            int start=i+1;
            int end =len-1;
            while(start<end){
                int sum=nums[start]+nums[end]+nums[i];
                if(sum==target){
                    return target;
                }else if(sum<target){
                   if(target-sum<min){
                       min=target-sum;
                       res=sum;
                   }
                    start++;
                }else{
                    if(sum-target<min){
                        min=sum-target;
                        res=sum;
                    }
                    end--;
                }
            }
        }
        return res;
    }