#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")


char buf[1010];

vector<int> rd(char c) {
  scanf("%s", buf);
  const int M = strlen(buf);
  vector<int> A(M);
  for (int i = 0; i < M; ++i) {
    A[i] = (buf[i] == c) ? 1 : 0;
  }
  return A;
}

vector<int> mul(const vector<int> &A0, const vector<int> &A1) {
  const int M0 = A0.size();
  const int M1 = A1.size();
  const int M = M0 / __gcd(M0, M1) * M1;
  vector<int> B(M);
  for (int i = 0; i < M; ++i) {
    B[i] = A0[i % M0] & A1[i % M1];
  }
  return B;
}

int main() {
  int K;
  for (; ~scanf("%d", &K); ) {
    const auto A0 = rd('T');
    const auto A1 = rd('T');
    const auto A2 = rd('P');
    const auto A3 = rd('C');
    const auto B0 = mul(A0, A1);
    const auto B1 = mul(A2, A3);
    const int M0 = B0.size();
    const int M1 = B1.size();
    const int G = __gcd(M0, M1);
// cerr<<"M0 = "<<M0<<", M1 = "<<M1<<endl;
// cerr<<B0<<endl<<B1<<endl;
    
    vector<Int> nxt(M1, M1);
    for (int i = 0; i < M1; ++i) if (B1[i]) {
      nxt[i] = 0;
    }
    for (int r = 0; r < G; ++r) {
      int cnt = 0;
      for (int i = r; ; ) {
        int j = (i - M0) % M1;
        if (j < 0) j += M1;
        chmin(nxt[j], 1 + nxt[i]);
        if (r == j) if (++cnt == 2) break;
        i = j;
      }
    }
// cerr<<"nxt = "<<nxt<<endl;
    
    priority_queue<Int, vector<Int>, greater<Int>> que;
    for (int i = 0; i < M0; ++i) if (B0[i]) {
      const Int q = nxt[i % M1];
      if (q < M1) {
        que.push(i + M0 * q);
      }
    }
    
    Int ans = -1;
    for (int k = 0; k < K; ++k) {
      if (!que.size()) {
        ans = -2;
        break;
      }
      ans = que.top();
      que.pop();
      const Int q = nxt[(ans + M0) % M1];
// if(K<=100)cerr<<ans<<": "<<ans%M0<<" "<<ans%M1<<"; "<<q<<endl;
      if (q < M1) {
        que.push(ans + M0 + M0 * q);
      }
    }
    printf("%lld\n", ans + 1);
  }
  return 0;
}