九度 1369 字符串的排列

package com.wangzhu.njupt;



import java.io.BufferedInputStream;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.StreamTokenizer;

import java.util.Arrays;



/**

 * 还有重复的字符数组的全排列

 * 

 * @ClassName: Main1369

 * @Description: TODO

 * @author 王竹

 * @date 2014-10-5 下午3:04:55

 * 

 */

public class Main1369 {



    /**

     * @param args

     * @throws IOException

     */

    public static void main(String[] args) throws IOException {

        //System.setIn(new FileInputStream("data.in"));

        StreamTokenizer in = new StreamTokenizer(new BufferedInputStream(

                System.in));

        while (in.nextToken() != StreamTokenizer.TT_EOF) {

            String str = in.sval;

            char[] buf = str.toCharArray();

            Arrays.sort(buf);

            int len = buf.length;

            boolean[] flagArr = new boolean[len];

            Arrays.fill(flagArr, true);

            char[] res = new char[len];

            dfs(0, len, buf, res, flagArr);

        }

    }



    /**

     * 输入：<br/>

     * abc<br/>

     * BCA<br/>

     * 输出：<br/>

     * abc<br/>

     * acb<br/>

     * bac<br/>

     * bca<br/>

     * cab<br/>

     * cba<br/>

     * ABC<br/>

     * ACB<br/>

     * BAC<br/>

     * BCA<br/>

     * CAB<br/>

     * CBA<br/>

     */

    /**

     * 

     * @param dep

     * @param maxDep

     * @param buf

     * @param res

     * @param flagArr

     */

    private static void dfs(int dep, int maxDep, char[] buf, char[] res,

            boolean[] flagArr) {

        if (dep == maxDep) {

            System.out.println(new String(res));

            return;

        }

        for (int i = 0; i < maxDep; i++) {

            if (!flagArr[i]

                    && (i != 0 && buf[i] == buf[i - 1] && flagArr[i - 1])) {

                // 当有重复的时候

                continue;

            }

            flagArr[i] = false;

            res[dep] = buf[i];

            dfs(dep + 1, maxDep, buf, res, flagArr);

            flagArr[i] = true;

        }

    }

}