| using namespace std; | |
| // https://leetcode.com/problems/3sum-closest/ | |
| class Solution { | |
| public: | |
| int threeSumClosest(vector<int>& nums, int target) { | |
| int result = -1; | |
| int minDiffSoFar = INT32_MAX; | |
| if (nums.size() < 3) { | |
| return result; | |
| } | |
| else if (nums.size() == 3) { | |
| return (nums[0] + nums[1] + nums[2]); | |
| } | |
| std::sort(nums.begin(), nums.end()); | |
| int n = nums.size(); | |
| for (int i = 0; i < n - 2; i++) { | |
| int a = nums[i]; | |
| int start = i + 1; | |
| int end = n - 1; | |
| while (start < end) { | |
| assert(i != start); | |
| assert(i != end); | |
| assert(start != end); | |
| int b = nums[start]; | |
| int c = nums[end]; | |
| int sum = a + b + c; | |
| int diff = sum - target; | |
| int absDiff = abs(diff); | |
| if (absDiff < minDiffSoFar) { | |
| minDiffSoFar = absDiff; | |
| result = sum; | |
| } | |
| if (diff > 0) { | |
| end--; | |
| } | |
| else if(diff < 0) { | |
| start++; | |
| } | |
| if (diff == 0) { | |
| return target; | |
| } | |
| } | |
| } | |
| return result; | |
| } | |
| }; | |
| int _16(int argc, _TCHAR* argv[]) | |
| { | |
| Solution s; | |
| vector<int> input = { 1,1,1,1 }; | |
| printf("%d\n", s.threeSumClosest(input, 0)); | |
| return 0; | |
| } |