用1、2、3、3、4、5这六个数字，用java写一个程序，打印出所有不同的排列 要求："4"不能在第三位，"3"与"5"不能相连。

用1、2、3、3、4、5这六个数字，用java写一个程序，打印出所有不同的排列 要求："4"不能在第三位，"3"与"5"不能相连。

递归：

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import java.util.ArrayList;import java.util.List;public class Test1 { public static void f(String in, ArrayList al) {        if (al.size() == 1) {            String tmp = in ;            if (!(tmp.contains("35") || tmp.contains("53") || tmp.indexOf('4') == 2)) {                System.out.println(tmp);            }        } else {            ArrayList hsc = (ArrayList) al.clone();            if (in.length() != 0) {                hsc.remove(in.substring(in.length() - 1));            }            for (Object i : hsc) {                f(in + i, hsc);            }        }    } public static void ff(String in, ArrayList<String> al){ if (al.size()==1) {if (!(in.contains("35")||in.contains("53")||in.indexOf("4")==2)) {System.out.println(in);}} else {ArrayList<String> hsc=(ArrayList<String>) al.clone();if (in.length()!=0) {hsc.remove(in.substring(in.length()-1));}for (String string : hsc) {ff(in+string,hsc);}} }public static void main(String args[]) {  ArrayList<String> al = new ArrayList<String>();        al.add("1");        al.add("2");        al.add("3");        al.add("4");        al.add("5");        al.add("6");        f("", al);}}

?循环遍历：

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import java.util.ArrayList;public class Test2 {public static void main(String args[]) {int[] nums = { 1, 2, 2, 3, 4, 5 };for (int i = 0; i < nums.length; i++) {for (int j = 0; j < nums.length; j++) {if (i == j || (nums[i] * nums[j] == 15))continue;for (int k = 0; k < nums.length; k++) {if (k == i || k == j || (nums[j] * nums[k] == 15)|| nums[k] == 4) {continue;}for (int m = 0; m < nums.length; m++) {if (m == k || m == i || m == j|| (nums[k] * nums[m] == 15)) {continue;}for (int n = 0; n < nums.length; n++) {if (n == m || n == k || n == i || n == j|| (nums[m] * nums[n] == 15)) {continue;}for (int l = 0; l < nums.length; l++) {if (l == n || l == m || l == k || l == j|| l == i || (nums[n] * nums[l] == 15)) {continue;}System.out.println(nums[i] + "" + nums[j] + ""+ nums[k] + "" + nums[m] + "" + nums[n]+ "" + nums[l]);}}}}}}}}