ac代码：

#include <iostream>
#include <cmath>
#include <cstring>
#include <cctype>
#include <algorithm>
#include <stdlib.h>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <sstream>
using namespace std;
typedef long long ll;
int s[10];
bool judge(int a)
{
    int k=a,c=10000;
    if(k/100000) return false;//超过五位数
    while(c!=0)
    {
        s[k/c]++;
        if(s[k/c]>1) return false;
        k%=c;
        c/=10;
    }
    return true;
}
int main()
{
    int n,num=0;
    //freopen("/Users/zhangkanqi/Desktop/11.txt","r",stdin);
    while(scanf("%d",&n)==1&&n!=0)
    {
        num++;
        if(num!=1)
            printf("\n");
        int b,ans=0;
        for(b=1234;b<=49876;b++)
        {
            memset(s,0,sizeof(s));
            bool flag1=judge(b);
            if(!flag1) continue;
            bool flag2=judge(n*b);
            if(flag2)
            {
                ans++;
                printf("%05d / %05d = %d\n",n*b,b,n);
            }
        }
        if(ans==0)
            printf("There are no solutions for %d.\n",n);
    }
    return 0;
}

网上的代码：

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
bool com(char a, char b)
{
    return a>b;
}
char ans[11]="9876543210";
char s[11];
int main()
{
    int n, pro, m=0;
    bool flag=false;
    while(scanf("%d", &n)!=EOF&&n)
    {
        if(m>0) printf("\n");
        m++;//输出技巧
        flag=false;
        for(int i=1234; i<=50000; i++)
        {
            pro=n*i;
            if(pro>98765)  break;
            if(i<10000)
                sprintf(s, "%d%d%d", 0, i, pro);
            else
                sprintf(s, "%d%d", i, pro);
            sort(s, s+10, com);
            if(strcmp(s, ans)==0)
            {
                printf("%d / %05d = %d\n", pro, i, n);
                flag=true;
            }
        }
        if(!flag)
            printf("There are no solutions for %d.\n", n);
    }
    return 0;
}