POJ3087(模拟)

#include"iostream"
#include"string"
#include"map"
using namespace std;
map<string,bool> mp;
int main()
{    
    int t;
    cin>>t;
    int test=0;
    while(++test<=t)
    {
        int step=0;
        mp.clear();
        int l;
        cin>>l;
        string s1;
        string s2;
        string s3;
        string s12="";
        cin>>s1;
        cin>>s2;
        cin>>s3;
        
        while(true)
        {
            for(int i=0;i<l;i++)
            {
                s12+=s2[i];
                s12+=s1[i];
            }
            
            
            step++;
            if(s12.compare(s3)==0)
            {
                cout<<test<<" "<<step<<endl;
                break;
            }
            else if(mp[s12]==true)
            {
                cout<<test<<" "<<-1<<endl;
                break;
            }
            mp[s12]=true;
            int i;
            s1.clear();
            s2.clear();
            
            for(i=0;i<l;i++)
            {
                s1+=s12[i];
            }
            for(;i<2*l;i++)
            {
                s2+=s12[i];
            }
            s12.clear();
        }
        
    }
    
    return 0;
}