荷兰国旗问题

public class helanguoqi {static void paixu(int[] a){int begin = 0;int end = a.length-1;int current = 0;while(current<=end){if(a[current]==0){int temp = a[begin];a[begin] = a[current];a[current] = temp;begin++;current++;}else if(a[current]==1){current++;}else if(a[current]==2){int temp = a[current];a[current] = a[end];a[end] = temp;end--;}}for(int i=0;i<a.length;i++){System.out.print(a[i]+" ");}}public static void main(String[] args) {int[] a={2,0,1,2,0,1,1,0,2,1};paixu(a);}}