目录
1.颜色分类
class Solution { public: void sortColors(vector<int>& nums) { int n = nums.size(); int left = -1, right = n, i = 0; while(i < right) { if(nums[i] == 2) { --right; swap(nums[i], nums[right]); } else if(nums[i] == 0) { ++left; swap(nums[i], nums[left]); ++i; } else ++i; } } };