#include #include #include #include #include #include #include #include #include #include #include #include #include #include #define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl; #define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } using namespace std; typedef long long ll; template vector> vec2d(int n, int m, T v){ return vector>(n, vector(m, v)); } template vector>> vec3d(int n, int m, int k, T v){ return vector>>(n, vector>(m, vector(k, v))); } template void print_vector(vector v, char delimiter=' '){ if(v.empty()) { cout << endl; return; } for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter; cout << v.back() << endl; } using mint = atcoder::modint1000000007; ostream& operator<<(ostream& os, const mint& m){ os << m.val(); return os; } int main(){ ios::sync_with_stdio(false); cin.tie(0); cout << setprecision(10) << fixed; ll n; cin >> n; string k; cin >> k; mint ans = 0; if(n == 0){ for(int i = 0; i < 8; i++){ if(k[i] == '-') continue; ans += 1; } cout << ans << endl; return 0; } for(int i = 0; i < 8; i++){ if(k[i] == '-') continue; int c = __builtin_popcount(i); mint ave = mint(c)/4; mint ave_other = 1-ave; mint m = mint(4).pow(n-1); mint sum = mint(2).pow(n-1)-1; ans += mint(4).pow(n)*(mint(2).pow(n-1)+1); { // p s_i qの最上位が1 ans += (ave-ave_other)*sum*m*c; } { // p s_i qの最上位が0 ans += (ave_other-ave)*sum*m*(4-c); } } cout << ans << endl; }