#line 2 "/home/seekworser/.cpp_lib/competitive_library/competitive/std/std.hpp" #include #ifndef LOCAL_TEST #pragma GCC target ("avx") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native") #endif // LOCAL_TEST using namespace std; // 型名の短縮 using ll = long long; using pii = pair; using pll = pair; using vi = vector; using vvi = vector; using vvvi = vector; using vl = vector; using vvl = vector; using vvvl = vector; using vb = vector; using vvb = vector; using vvvb = vector; using vc = vector; using vvc = vector; using vvvc = vector; using vd = vector; using vvd = vector; using vvvd = vector; using vs = vector; using vvs = vector>; using vvvs = vector>>; template using priority_queue_min = priority_queue, greater>; // 定数の定義 constexpr double PI = 3.14159265358979323; constexpr int INF = 100100111; constexpr ll INFL = 3300300300300300491LL; float EPS = 1e-8; double EPSL = 1e-16; bool eq(const double x, const double y) { return abs(x - y) < EPSL; } bool eq(const float x, const float y) { return abs(x - y) < EPS; } template bool eq(const T x, const T y) { return x == y; } template bool neq(const T x, const T y) { return !(eq(x, y)); } template bool ge(const T x, const T y) { return eq(x, y) || (x > y); } template bool le(const T x, const T y) { return eq(x, y) || (x < y); } template bool gt(const T x, const T y) { return !(le(x, y)); } template bool lt(const T x, const T y) { return !(ge(x, y)); } constexpr int MODINT998244353 = 998244353; constexpr int MODINT1000000007 = 1000000007; // 入出力高速化 struct Nyan { Nyan() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(18); } } nyan; // 汎用マクロの定義 #define all(a) (a).begin(), (a).end() #define sz(x) ((int)(x).size()) #define rep(i, n) for(ll i = 0, i##_len = ll(n); i < i##_len; ++i) // 0 から n-1 まで昇順 #define repi(i, s, t) for(ll i = ll(s), i##_end = ll(t); i < i##_end; ++i) // s から t まで昇順 #define repis(i, s, t, step) for(ll i = ll(s), i##_end = ll(t); i < i##_end; i+=step) // s から t まで stepずつ #define repir(i, s, t, step) for(ll i = ll(s), i##_end = ll(t); i > i##_end; i+=step) // s から t まで stepずつ #define repe(a, v) for(auto& a : (v)) // v の全要素(変更可能) #define smod(n, m) ((((n) % (m)) + (m)) % (m)) // 非負mod #define sdiv(n, m) (((n) - smod(n, m)) / (m)) // 非負div #define uniq(a) {sort(all(a)); (a).erase(unique(all(a)), (a).end());} // 重複除去 void Yes(bool b) { cout << (b ? "Yes\n" : "No\n"); return; }; void YES(bool b) { cout << (b ? "YES\n" : "NO\n"); return; }; template T max(array& a) { return *max_element(all(a)); }; template T min(array& a) { return *min_element(all(a)); }; template T max(vector& a) { return *max_element(all(a)); }; template T min(vector& a) { return *min_element(all(a)); }; template T sum(vector& a, T zero = T(0)) { T rev = zero; rep(i, sz(a)) rev += a[i]; return rev; }; // modでのpow ll powm(ll a, ll n, ll mod=INFL) { ll res = 1; while (n > 0) { if (n & 1) res = (res * a) % mod; if (n > 1) a = (a * a) % mod; n >>= 1; } return res; } // 整数Sqrt ll sqrtll(ll x) { assert(x >= 0); ll hi(x), lo(0); while (hi != lo) { ll y = (hi + lo + 1) / 2; if (y <= x/y) lo = y; else hi = y - 1; } return lo; } template inline bool chmax(T& M, const T& x) { if (M < x) { M = x; return true; } return false; } // 最大値を更新(更新されたら true を返す) template inline bool chmin(T& m, const T& x) { if (m > x) { m = x; return true; } return false; } // 最小値を更新(更新されたら true を返す) int digit(ll x, int d=10) { int rev=0; while (x > 0) { rev++; x /= d;}; return rev; } // xのd進数桁数 /** * @brief std.hpp * @docs docs/std/std.md */ #line 3 "/home/seekworser/.cpp_lib/competitive_library/competitive/std/io.hpp" // 演算子オーバーロード(プロトタイプ宣言) template inline istream& operator>>(istream& is, pair& p); template inline istream& operator>>(istream& is, vector& v); template inline ostream& operator<<(ostream& os, const pair& p); template inline ostream& operator<<(ostream& os, const vector& v); template ostream &operator<<(ostream &os, const map &mp); template ostream &operator<<(ostream &os, const set &st); template ostream &operator<<(ostream &os, const multiset &st); template ostream &operator<<(ostream &os, queue q); template ostream &operator<<(ostream &os, deque q); template ostream &operator<<(ostream &os, stack st); template ostream &operator<<(ostream &os, priority_queue pq); // 演算子オーバーロード template inline istream& operator>>(istream& is, pair& p) { is >> p.first >> p.second; return is; } template inline istream& operator>>(istream& is, vector& v) { repe(x, v) is >> x; return is; } template inline ostream& operator<<(ostream& os, const pair& p) { os << p.first << " " << p.second; return os; } template inline ostream& operator<<(ostream& os, const vector& v) { rep(i, sz(v)) { os << v.at(i); if (i != sz(v) - 1) os << " "; } return os; } template ostream &operator<<(ostream &os, const map &mp) { for (auto &[key, val] : mp) { os << key << ":" << val << " "; } return os; } template ostream &operator<<(ostream &os, const set &st) { auto itr = st.begin(); for (int i = 0; i < (int)st.size(); i++) { os << *itr << (i + 1 != (int)st.size() ? " " : ""); itr++; } return os; } template ostream &operator<<(ostream &os, const multiset &st) { auto itr = st.begin(); for (int i = 0; i < (int)st.size(); i++) { os << *itr << (i + 1 != (int)st.size() ? " " : ""); itr++; } return os; } template ostream &operator<<(ostream &os, queue q) { while (q.size()) { os << q.front() << " "; q.pop(); } return os; } template ostream &operator<<(ostream &os, deque q) { while (q.size()) { os << q.front() << " "; q.pop_front(); } return os; } template ostream &operator<<(ostream &os, stack st) { while (st.size()) { os << st.top() << " "; st.pop(); } return os; } template ostream &operator<<(ostream &os, priority_queue pq) { while (pq.size()) { os << pq.top() << " "; pq.pop(); } return os; } template inline vector& operator--(vector& v) { repe(x, v) --x; return v; } template inline vector& operator++(vector& v) { repe(x, v) ++x; return v; } template void print_sep_end(string sep, string end, const T& val) { (void)sep; cout << val << end; }; template void print_sep_end(string sep, string end, const T1 &val, const T2 &...remain) { cout << val << sep; print_sep_end(sep, end, remain...); }; template void print(const T&...args) {print_sep_end(" ", "\n", args...);}; #define debug(...) debug_func(0, #__VA_ARGS__, __VA_ARGS__) // debug print #ifdef LOCAL_TEST template void debug_func(int i, T name) { (void)i; (void)name; cerr << endl; } template void debug_func(int i, const T1 &name, const T2 &a, const T3 &...b) { for ( ; name[i] != ',' && name[i] != '\0'; i++ ) cerr << name[i]; cerr << ":" << a << " "; debug_func(i + 1, name, b...); } #endif #ifndef LOCAL_TEST template void debug_func(const T &...) {} #endif /** * @brief io.hpp * @docs docs/std/io.md */ #line 3 "answer.cpp" int main() { int n,m; cin >> n >> m; int m1 = m / 2; int m2 = m - m1; vi a(m), b(m); rep(i, m) { cin >> a[i] >> b[i]; } --a; --b; ll c(0); rep(i, n) { int ci; cin >> ci; if (ci == 1) c += 1LL << i; } unordered_map mp; rep(bt, 1 << m1) { ll l(0); rep(i, m1) { if ((bt >> i) & 1) { l ^= 1LL << a[i]; l ^= 1LL << b[i]; } } if (mp.count(l)) chmin(mp[l], __popcount(bt)); else mp[l] = __popcount(bt); } int ans = INF; rep(bt, 1 << m2) { ll r(0); rep(i, m2) { if ((bt >> i) & 1) { r ^= 1LL << a[m1+i]; r ^= 1LL << b[m1+i]; } } r ^= c; if (mp.count(r)) chmin(ans, mp[r] + __popcount(bt)); } if (ans != INF) print(ans); else print(-1); }