如何产生所有的数字序列。
比如1 2 3
结果：
1 2 3
1 3 2
2 1 3
2 3 1
3 1 2
3 2 1
[解决办法]
void perm (int [] source, int [] result, int index) {
for (int i = 0; i < source.length; i ++) {
for (int j = 0; j < index; j++) {
if (source[i] == result[j])
continue;
break;
}
result[index] = source[i];
break;
}
if (index == source.length -1)
return;
perm(source, result, index+1);
}
int[] source = {1, 2, 3};
int[] result = new int[3];
perm(source, result, 0);
#include <stdio.h>
#include <string.h>
char string[]="123456789a";
int used[10]={0};
char output[10];
int length;
void Fun(int d)
{
int i;
for(i=0;i<=length;i++)
{
if(!used[i])
{
used[i]=1;
output[d]=string[i];
if(d==length)
{
for(d=0;d<length;d++)
{
if(output[d]=='a')
printf("10 ");
else printf("%c ",output[d]);
}
if(output[length]=='a')
printf("10\n");
else
printf("%c\n",output[length]);
}
else
Fun(d+1);
used[i]=0;
}
}
}
int main()
{
int n;
scanf("%d",&n);
string[n]=0;
length=strlen(string)-1;
Fun(0);
return 0;
}
public class Test4 {
public static void main(String[] args) {
String test = "123";
char[] chars = test.toCharArray();
allSort(chars, 0, chars.length - 1);
}
private static StringBuilder TEMP = new StringBuilder();
public static void allSort(char[] buf, int start, int end) {
if (start == end) {
for (int i = 0; i <= end; i++) {
TEMP.append(buf[i]);
}
numberChecker();
} else {
for (int i = start; i <= end; i++) {
char temp = buf[start];
buf[start] = buf[i];
buf[i] = temp;
allSort(buf, start + 1, end);
temp = buf[start];
buf[start] = buf[i];
buf[i] = temp;
}
}
}
private static void numberChecker() {
System.out.println(TEMP);
TEMP.replace(0, TEMP.length(), "");
}
}