将一串字符串全排列输出（回溯法）

直接上代码

//Author      :Freetion
//E-mail      :Freetion@live.com
//file        :

#include <stdio.h>
#include <string.h>
char str[1000], stack[1000];;
char ch[256];
int count[256];
int char_num, str_len;

void deal_str()
{
    int s[256];
    memset(s, 0, sizeof(s));
    memset(count, 0, sizeof(count));
    str_len = strlen(str);
    for (int i = 0; i < str_len; i ++)
        s[str[i]] ++;
    char_num = 0;
    for (int i = 0; i < 256; i ++)
    {
        if (s[i])
        {
            count[char_num] = s[i];
            ch[char_num ++] = i;
        }
    }
    return;
}

void found(int depth)
{
    
    if (depth == str_len)
    {
        for (int i = 0; i < depth; i ++)
            putchar(ch[stack[i]]);
        puts("");
    }
    else
    {
        for (int i = 0; i < char_num; i ++)
        {
            if (count[i])
            {
                stack[depth] = i;
                count[i] --;
                found(depth +1);
                count[i] ++;
            }
        }
    }
    return;
}

int main()
{
    while (gets(str))
    {
        deal_str();
        found(0);
    }
    return 0;
}