Tony's Log

摘要： Similar strategy could be applied to 4Sum, as 2sum to 3sum, but that'll be O(n^3). Instead of 3 + 1, we can also divide it into 2 + 2. So the problem ... 阅读全文

摘要： Simply a variation of 3Sum:class Solution {public: int threeSumClosest(vector &num, int target) { int ret = 99999999999; std::sort(nu... 阅读全文

摘要： Now that you've solved 2sum, 3sum can be easily converted as 2sum.Also please note the while loops for i1 and i2: they are to make sure no duplicates.... 阅读全文