标签：des style c class blog code
Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero.
Note:
For example, given array S = {-1 0 1 2 -1 -4},
A solution set is:
(-1, 0, 1)
(-1, -1, 2)
#include<iostream> #include<vector> #include<algorithm> using namespace std; class Solution { vector<vector<int> > ret; public: void helper(vector<int> &num,vector<int>::size_type base) { vector<int>::size_type left = base + 1; vector<int>::size_type right = num.size() - 1; int com = num[base] * (-1); while(left < right) { int temp = num[left] + num[right]; if( temp > com ) right--; else if(temp < com) left++; else { vector<int> t; t.push_back(num[base]);t.push_back(num[left]);t.push_back(num[right]); ret.push_back(t); right--;left++; } } } vector<vector<int> > threeSum(vector<int> &num) { sort(num.begin(),num.end()); ///进行排序，运用迭代器～ for(vector<int>::size_type i = 0;i< num.size();i++) if(i > 0 && num[i] == num[i -1]) continue; else helper(num,i); return ret; } }; int main() { vector<int > t; t.push_back(-1);t.push_back(0);t.push_back(1);t.push_back(2);t.push_back(-1);t.push_back(-4); Solution s; vector<vector<int> > v = s.threeSum(t); cout<<v.size(); }
leetcode -- 3sum,布布扣,bubuko.com
标签：des style c class blog code
原文地址：http://www.cnblogs.com/berkeleysong/p/3754889.html
