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).
class Solution {
public:
int threeSumClosest(vector<int> &num, int target) {
sort(num.begin(),num.end());
int base = ,left = ,right = num.size() - ;
int minSum = num[base] + num[left] + num[right];int mindistance = abs(minSum - target);
for(base = ;base< num.size();base++)
{
left = base + ; right = num.size() -;
while(left < right)
{
int sum = num[base] + num[left] + num[right];
int dis = sum - target ;
if(dis > )
{
right--;
}else if(dis <)
{
left++;
}else
{
return sum;
}
if(abs(dis) < mindistance)
{
minSum = sum;
mindistance = abs(dis);
}
}
}
return minSum;
}
};