LeetCode 75. Sort Colors (O(n) one pass实现)

代码：

class Solution {public:    void sortColors(int A[], int n)     {        int red=0, white=0;        for (int i = 0; i < n; ++ i)        {        if (A[i] == WHITE)        {        A[i] = BLUE;        A[white ++] = WHITE;        } else if (A[i] == RED)        {        A[i] = BLUE;        A[white ++] = WHITE;        A[red ++] = RED;        }        }    }private:const int RED = 0;const int WHITE = 1;const int BLUE = 2;};