vscode是一个外表很高冷的姑娘，你需要对她投入很多，她才会慢慢接纳你。她是一个善良却保守的姑娘，每一次你提出新要求时，都需要折腾折腾她一波，她才能同意你。

// C Call
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int num = 0;

void swap(char *a, char *b)
{
  char temp = *a;
  *a = *b;
  *b = temp;
}

void whole_arrangement(char ch[], int k, int len)
{
  int i;
  if (k == len)
  {
    printf("%s", ch);
    num++;
    printf(", ");
    return;
  }
  else
  {
    for (i = k; i <= len; i++)
    {
      swap(&ch[k], &ch[i]);
      whole_arrangement(ch, k + 1, len);
      swap(&ch[k], &ch[i]);
    }
  }
}

int main()
{
  char ch[] = "abc";
  whole_arrangement(ch, 0, strlen(ch) - 1);
  printf("\nCOUNT: %d\n", num);
  system("pause");
  return 0;
}

// Java Call
// Main.java
public class Main {
  public static void main(String[] args) {
    String ch = "abc";
    wholeArrangement(ch.toCharArray(), 0);

  }

  public static void wholeArrangement(char[] ch, int k) {
    int i;
    if (k == ch.length - 1) {
      System.out.print(ch);
      System.out.print(", ");
      return;
    } else {
      for (i = k; i <= ch.length - 1; i++) {
        char temp = ch[k];
        ch[k] = ch[i];
        ch[i] = temp;
        wholeArrangement(ch, k + 1);
        temp = ch[k];
        ch[k] = ch[i];
        ch[i] = temp;
      }
    }
  }
}

# python Call
from typing import List


def whole_arrangement(ch: List[str], k: int) -> None:
    if k == len(ch):
        print("".join(ch), end='')
        print(", ", end='')
        return
    else:
        for i in range(k, len(ch)):
            temp = ch[k]
            ch[k] = ch[i]
            ch[i] = temp
            whole_arrangement(ch, k+1)
            temp = ch[k]
            ch[k] = ch[i]
            ch[i] = temp


def main() -> None:
    ch = "abcde"
    whole_arrangement(list(ch), 0)


if __name__ == "__main__":
    main()