#include <vector>
#include <string>
#include <iostream>
#include <fstream>
#include <sstream>
#include <list>
#include <algorithm>
#include <sstream>
#include <set>
#include <cmath>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <stack>
#include <queue>
#include <cstdio>
//#include <cstdlib>
#include <cstring>
#include <numeric>
#include <bitset>
#include <deque>
#include <memory>

const long long LINF = (5e17);
const int INF = 1000000000;
#define EPS 1e-7
const int MOD = 1000000007;

using namespace std;

class TaroFillingAStringDiv1 {

public:

	int getNumber(int N, vector <int> position, string value) {
		if (N==0)
			return 1;
		typedef pair<int, char> P;
		vector<P> m;
		for (int i=0; i<position.size(); ++i)
			m.push_back(P(position[i], value[i]));
		sort(m.begin(), m.end());
		long long ans = 1;
		for (int i=1; i<m.size(); ++i) {
			int d = m[i].first - m[i-1].first - 1;
			if ( (d&1) == (m[i].second != m[i-1].second) )
				ans = (ans * (d+1) )%MOD;
		}
		return (int)ans;
	}


	// BEGIN CUT HERE
public:
	void run_test(int Case) { if ((Case == -1) || (Case == 0)) test_case_0(); if ((Case == -1) || (Case == 1)) test_case_1(); if ((Case == -1) || (Case == 2)) test_case_2(); if ((Case == -1) || (Case == 3)) test_case_3(); }
private:
	template <typename T> string print_array(const vector<T> &V) { ostringstream os; os << "{ "; for (typename vector<T>::const_iterator iter = V.begin(); iter != V.end(); ++iter) os << '\"' << *iter << "\","; os << " }"; return os.str(); }
	void verify_case(int Case, const int &Expected, const int &Received) { cerr << "Test Case #" << Case << "..."; if (Expected == Received) cerr << "PASSED" << endl; else { cerr << "FAILED" << endl; cerr << "\tExpected: \"" << Expected << '\"' << endl; cerr << "\tReceived: \"" << Received << '\"' << endl; } }
	void test_case_0() { int Arg0 = 3; int Arr1[] = {1, 3}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); string Arg2 = "AB"; int Arg3 = 2; verify_case(0, Arg3, getNumber(Arg0, Arg1, Arg2)); }
	void test_case_1() { int Arg0 = 4; int Arr1[] = {2, 1, 3, 4}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); string Arg2 = "ABBA"; int Arg3 = 1; verify_case(1, Arg3, getNumber(Arg0, Arg1, Arg2)); }
	void test_case_2() { int Arg0 = 25; int Arr1[] = {23, 4, 8, 1, 24, 9, 16, 17, 6, 2, 25, 15, 14, 7, 13}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); string Arg2 = "ABBBBABABBAAABA"; int Arg3 = 1; verify_case(2, Arg3, getNumber(Arg0, Arg1, Arg2)); }
	void test_case_3() { int Arg0 = 305; int Arr1[] = {183, 115, 250, 1, 188, 193, 163, 221, 144, 191, 92, 192, 58, 215, 157, 187, 227, 177, 206, 15, 272, 232, 49, 11, 178, 59, 189, 246}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); string Arg2 = "ABAABBABBAABABBBBAAAABBABBBA"; int Arg3 = 43068480; verify_case(3, Arg3, getNumber(Arg0, Arg1, Arg2)); }

	// END CUT HERE


};



// BEGIN CUT HERE

int main() {

	TaroFillingAStringDiv1 ___test;

	___test.run_test(-1);

}

// END CUT HERE