codeforce - xenia and divisors

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int ara[n+1],o=0,t=0,tr=0,f=0,s=0;
    bool fl= false;
    for(int i=0;i<n;i++)
    {
        cin>>ara[i];
        if(ara[i]==5 || ara[i]==7)fl=true;
        if(ara[i]==1)o++;
        if(ara[i]==2)t++;
        if(ara[i]==3)tr++;
        if(ara[i]==4)f++;
        if(ara[i]==6)s++;
    }
    //cout<<o<<" "<<t<<" "<<tr<<" "<<f<< " "<<s<<endl;
    if(!fl && tr<=s && t<=f+s && o==t+tr)
    {
        for(int i=0;i<tr;i++)
            cout<<"1 3 6"<<endl;
        for(int i=0;i<f;i++)
            cout<<"1 2 4"<<endl;
        for(int i=tr;i<s;i++)
            cout<<"1 2 6"<<endl;
    }
    else cout<<"-1"<<endl;

}