[LeetCode]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.

    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).

public class Solution {
    public int threeSumClosest(int[] num, int target) {
    	 if(num == null||num.length<3){
         	System.exit(0);
         }
         Arrays.sort(num);
         int res =0;
         int mini = 2000000000; 
        for(int i=0;i<num.length-2;i++){
           
           int ta = target - num[i];
     	   int left = i+1;
     	   int right = num.length - 1;
     	   
     	   while(left<right){
     		   if(ta == num[left]+num[right]){
     			   	return target;
     		   }else if(ta > num[left]+num[right]){
     			   if(mini>ta-num[left]-num[right]){
     				   res = num[left]+num[right]+num[i];
     				   mini = ta-num[left]-num[right];
     			   }
     			   left++;
     		   }else{
     			   if(mini>num[left]+num[right]-ta){
     				   res = num[left]+num[right]+num[i];
     				   mini = num[left]+num[right]-ta;
     			   }
     			   right--;
     		   }
     	   }
        }
		return res;
    }
}