C

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int m;
    cin>>m;

    vector<string> s(3);
    cin>>s[0]>>s[1]>>s[2];

    for(auto &e: s)
        e = e+e+e;

    int ans = 1e9;

    for(int i=0; i<3*m; i++)
    {
        for(int j=0; j<3*m; j++)
        {
            for(int k=0; k<3*m; k++)
            {
                if(i==j || j==k || i==k)        continue;

                if(s[0][i]!=s[1][j] || s[1][j]!=s[2][k] || s[0][i]!=s[2][k])        continue;

                ans = min(ans, max({i, j, k}));
            }
        }
    }

    if(ans == 1e9)      ans = -1;

    cout<<ans<<"\n";
}