leetcode刷题20

public static int solution(int[] nums, int target) {
        Arrays.sort(nums);
        int num=nums[1]+nums[0]+nums[2];
        for(int i=0;i<nums.length-2;i++){
            int a=i+1;
            int b=nums.length-1;
            while(a<b){
                int sum=nums[i]+nums[a]+nums[b];
                if(Math.abs(sum-target)<Math.abs(num-target)){
                    num=sum;
                }
                if(sum>target){
                    while (a<b && nums[b] == nums[b-1]) b--;
                    b--;
                }else if(sum<target){
                    while (a<b && nums[a] == nums[a+1]) a++;
                    a++;
                }else{
                    return target;
                }
            }
        }
        return num;
    }