题解 | 牛的品种排序II

import java.util.*;


public class Solution {
    public int[] sortCows (int[] cows) {
        final int n = cows.length;
        int i = 0;
        int j = n - 1;
        while (i < j) {
            while (i < j && cows[i] == 0) {
                ++i;
            }
            while (i < j && cows[j] != 0) {
                --j;
            }
            if (i < j) {
                cows[j--] = cows[i];
                cows[i++] = 0;
            }
        }
        j = n - 1;
        while (i < j) {
            while (i < j && cows[i] == 1) {
                ++i;
            }
            while (i < j && cows[j] == 2) {
                --j;
            }
            if (i < j) {
                cows[i++] = 1;
                cows[j--] = 2;
            }
        }
        return cows;
    }
}