int [] a = {1,2,3};
for( int i=0;i<a.length;i++){
for( int j=0;j<a.length;j++){
for( int k=0;k<a.length;k++){
for ....
.
.
.
System.out.println(a[i]+""+a[j]+""+a[k]+ ...+a[n]);
.
.
.
}
}
}
} 嵌套n层循环,如何用递归实现?
帮帮我吧,想了半天也没搞定! :(
for( int i=0;i<a.length;i++){
for( int j=0;j<a.length;j++){
for( int k=0;k<a.length;k++){
for ....
.
.
.
System.out.println(a[i]+""+a[j]+""+a[k]+ ...+a[n]);
.
.
.
}
}
}
} 嵌套n层循环,如何用递归实现?
帮帮我吧,想了半天也没搞定! :(
for( int i=0;i <a.length;i++){
for( int j=0;j <a.length;j++){
for( int k=0;k <a.length;k++){
for( int h=0;k <a.length;k++){
for( int l=0;k <a.length;k++){
System.out.println(a[i]+" "+a[j]+" "+a[k]+" "+a[h]+" "+a[l]);
}
}
}
}
}
public class Test3 {
public static void main(String[] args) {
int [] a = {1,2,3,4,5,6,7,8,9,10};
for (int i = 0; i < a.length; i++) {
for (int j = 0; j < a.length; j++) {
for (int k = 0; k < a.length; k++) {
for (int m = 0; m < a.length; m++) {
for (int n = 0; n < a.length; n++) {
System.out.println(a[i]+" "+a[j]+" "+a[k]+" "+a[m]+" "+a[n]);
}
}
}
}
}
}
}是把这个改成递归?
12
13 21
22
23 31
32
33 其实答案的个数就是 ,集合所有元素数m的n次方
{
public static void main(String[] args)
{
int [] a = {1,2,3,4};
String b="";
abc(a, b, 1);
}
public static void abc(int[] a, String b, int n)
{
String b1 = b;
for (int i = 0; i < a.length; i++)
{
b1= (b == "" ? "" : b + " ") + a[i];
if (n < a.length)
abc(a, b1, n+1);
else
System.out.println(b1);
}
}}
private char[] sequence; public SequenceGenerator(char[] elements, int sequenceLength) {
this.elements = elements;
this.sequence = new char[sequenceLength];
} public static void main(String[] args) {
new SequenceGenerator(new char[] { '1', '2', '3' }, 5).generate();
} public void generate() {
generate(0);
} private void generate(int index) {
for (int i = 0; i < elements.length; i++) {
sequence[index] = elements[i];
if (index + 1 < sequence.length) {
generate(index + 1);
} else {
System.out.println(String.valueOf(sequence));
}
}
}
}
int[] array; public Test(int[] array) {
this.array = array;
} public void printArray(int n) {
if (n == 1) {
for (int i = 0; i < array.length; i++) {
doSomething();
}
} else {
n -= 1;
for (int j = 0; j < array.length; j++) {
printArray(n);
}
} } private void doSomething() {
// TODO:add any thing you want to do;
} public static void main(String[] args) {
int[] a = { 1, 2, 3 };
Test t = new Test(a);
t.printArray(3); }
}
* @param args
*/
public static void main(String[] args) {
String [] a = {"1","2","3","4"};
int n=4;
System.out.println( printArr(a,n));
} private static String printArr(String[] a,int n) {
if(n<=1)
{
String ss="";
for (int i = 0; i < a.length; i++) {
ss=ss+a[i]+" ";
}
return ss;
}
else
{
String s=printArr( a, n-1);
String returnValue="";
for (int i = 0; i < a.length; i++) {
returnValue=returnValue+method(a[i],s);
}
return returnValue;
}
} private static String method(String i, String s) {
String value="";
String arr[]=s.split(" ");
for (int j = 0; j <arr.length; j++) {
value=value+i+arr[j]+" ";
}
return value;
}}
int ii,jj,kk;
kk++;
if kk > a.length {
kk = 0;
jj++;
}
if jj > a.length {
jj = 0;
ii++;
}
System.out.println(a[i]+","+a[j]+","+a[k]);
func(ii,jj,kk);
}
public static void recursionInsteadFor(int n , String str, char[] pk) {
if (n > pk.length) return;
if (n == pk.length) System.out.println(str);
for (int i = 0 ; i < pk.length ; ++ i)
recursionInsteadFor(n + 1, str + pk[i], pk);
}
public static void main(String[] args) {
char[] p = new char[] {'a','b','c','d','e'};
FromCSDN.recursionInsteadFor(0, "", p);
}}
*
*/
package houlei.test;import java.util.Collection;
import java.util.LinkedList;/**
* 该类创建于 2008-10-17 下午04:53:56
*
* @version 1.0.0
* @author 侯磊
*/
public class L { public static void main(String[] args) {
fun(3, new int[] { 1, 2, 3 }, null);
} /**
* @param level 嵌套的层次
* @param a 待传的数组
* @param rs 首次调用的时候,为null
*/
public static void fun(int level, int a[], int [] rs) {
if (rs == null) rs = new int[a.length];
for (int i = 0; i < a.length; i++) {
if (level <= 0) {
StringBuffer sb = new StringBuffer();
for(int k=0;k<rs.length;k++)sb.append(rs[k]);
System.out.println(sb.toString());
return;
} else {
rs[rs.length-level]=a[i];
fun(level - 1, a, rs);
}
}
}}