C++ 双指针遍历

题目：

class Solution {
     
public:    
int threeSumClosest(vector<int>& nums, int target) {
             
sort(nums.begin(),nums.end());        
int res = nums[0] + nums[1] + nums[2];//获取和最小值        
for(int ind = 0 ; ind < nums.size()-2; ind++){
                 
	int mid = ind + 1 , lar = nums.size()-1;            
	while(mid < lar){
                     
		int sum = nums[ind] + nums[mid] + nums[lar];
		if(target == sum) return sum;                
		if(abs(target - sum) < abs(target - res)) res = sum; 
		else if(sum < target) mid++;                
		else lar--;
	}
return res;
}

mid 和 lar 双指针遍历！