递归

/*
思路：递归
参数1 层数，第i层，层数9，就判断是不是符合要求
参数2 字符串类型，按照顺序应该是第一个数字，第二个数字，第三个数字

*/

#include <bits/stdc++.h>
using namespace std;

int nums[] = {0,1,2,3,4,   5,6,7,8,9};
int zw[] =   {0,0,0,0,0,   0,0,0,0,0};

/*
思路：递归
层数，第i层
层数9，就判断是不是可以计算
*/
void slj(int n,string s)
{
    if(n==9)
    {	
        int n1 = (s[0]-'0')*100 + (s[1]-'0')*10 + (s[2]-'0');
        int n2 = (s[3]-'0')*100 + (s[4]-'0')*10 + (s[5]-'0');
        int n3 = (s[6]-'0')*100 + (s[7]-'0')*10 + (s[8]-'0');
        if (n1*6 == n2*3  and n2*3 == n3*2)cout<<n1<<" "<<n2<<" "<<n3<<endl;
        
    }
    else{
        for(int i=1;i<=9;i++)
            {
                if(zw[i]==0)
                {
                    zw[i] = 1;
                    slj(n**** + char('0'+nums[i]));
                    zw[i] = 0;
                }
            }
        
        
    }

    
}

int main()
{

    slj(0,"");

	return 0;
}