这题怎么做呢，写个代码呗

这是C++的代码

#include<iostream>
using namespace std;
int main(){
    bool a[10];
    int sum=0;
    for(int i=123;i*3<=987;++i){
        for(int j=1;j<=9;++j)a[j]=0;
        a[i/100]=1;
        a[i/10%10]=1;
        a[i%10]=1;
        a[i*2/100]=1;
        a[i*2/10%10]=1;
        a[i*2%10]=1;
        a[i*3/100]=1;
        a[i*3/10%10]=1;
        a[i*3%10]=1;
        sum=0;
        for(int j=1;j<=9;++j)sum+=a[j];
        if(sum==9)cout<<i<<" "<<i*2<<" "<<i*3<<endl;
    }
}