sort colors

class Solution {
public:
    void sortColors(int A[], int n) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int left = 0;
        int right = n-1;
        
        int i=0;
        int j = n-1;
        
        while( i <= right )
        {
            if( A[i] == 0 ) 
            { 
                A[i] = A[left];
                A[left] = 0;
                left++;
                i++;
            }
            else if(A[i] == 1 ) { i++; }
            else
            {
                A[i] = A[right];
                A[right] = 2;
                right --;
            }
        }
        return;
    }

};