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#include <algorithm>
#include <cinttypes>
#include <cmath>
#include <cstdlib>
#include <cstdio>
#include <cstdint>
#include <deque>
#include <initializer_list>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using std::deque;
using std::initializer_list;
using std::make_pair;
using std::map;
using std::multiset;
using std::pair;
using std::priority_queue;
using std::reverse;
using std::set;
using std::sort;
using std::string;
using std::swap;
using std::unordered_map;
using std::unordered_set;
using std::vector;

typedef int8_t     int8;
typedef int16_t    int16;
typedef int32_t    int32;
typedef int64_t    int64;
typedef __int128_t int128;

template <typename T>
using priority_queue_max = std::priority_queue<T>;

template <typename T>
using priority_queue_min = std::priority_queue<T, std::vector<T>, std::greater<T>>;

const int32 oo = 1e9;
const int64 ooo = 1e18;

#define scan(args...) [&]{ return scanf(args); }();
#define elements(a) ((int32)(a).size())
#define TESTS  int32 _t; scan("%" SCNd32, &_t); while (_t--)

inline int64 castformorebits(int32 a)
{
    return (int64)a;
}

inline int128 castformorebits(int64 a)
{
    return (int128)a;
}

template <class INT>
inline INT abs(INT a)
{
    if (a >= 0) return a;
    return -a;
}

template <typename T>
T minimum(std::initializer_list<T>&& l)
{
    T answer = *(l.begin());

    for (auto a : l)
        if (a < answer)
            answer = a;

    return answer;
}

template <typename T>
T minimum(const vector<T>& l)
{
    T answer = *(l.begin());

    for (auto a : l)
        if (a < answer)
            answer = a;

    return answer;
}

template <typename T>
T maximum(std::initializer_list<T>&& l)
{
    T answer = *(l.begin());

    for (auto a : l)
        if (a > answer)
            answer = a;

    return answer;
}

template <typename T>
T maximum(const vector<T>& l)
{
    T answer = *(l.begin());

    for (auto a : l)
        if (a > answer)
            answer = a;

    return answer;
}

template <typename T>
inline void sort(T &data)
{
    sort(data.begin(), data.end());
}

template <typename T>
inline void reverse(T &data)
{
    reverse(data.begin(), data.end());
}

template <class INT>
INT fast_exponential(INT a, INT b, INT mod)
{
    INT result = 1;

    while (b > 0)
    {
        if (b % 2 == 1)
            result = (castformorebits(result) * a) % mod;
        a = (castformorebits(a) * a) % mod;
        b = b / 2;
    }

    return result;
}

// TODO: ++ --

struct int_mod
{
    int32 val;
    static int32 modulo;
    int_mod() : val(0) {}
    int_mod(int32 n) : val(n % modulo) {}

    int_mod& operator=(const int32& n)
    {
        val = n % modulo;
        return *this;
    }

    int_mod& operator+=(const int_mod &a)
    {
        val += a.val;
        if (val >= modulo)
            val -= modulo;
        return *this;
    }

    int_mod& operator-=(const int_mod &a)
    {
        val += modulo - a.val;
        if (val >= modulo)
            val -= modulo;
        return *this;
    }

    int_mod& operator*=(const int_mod &a)
    {
        val = (castformorebits(val) * a.val) % modulo;
        return *this;
    }

    int_mod& operator/=(const int_mod &a)
    {
        // Assume modulo is prime
        int32 inverse = fast_exponential(a.val, modulo-2, modulo);

        val = (castformorebits(val) * inverse) % modulo;
        return *this;
    }
};

int int_mod::modulo = 0;

inline int_mod operator+(const int_mod &a, const int_mod b)
{
    int_mod res;

    res.val = a.val + b.val;
    if (res.val >= int_mod::modulo)
        res.val -= int_mod::modulo;
    return res;
}

inline int_mod operator-(const int_mod &a, const int_mod &b)
{
    int_mod res;

    res.val = a.val - b.val + int_mod::modulo;
    if (res.val >= int_mod::modulo)
        res.val -= int_mod::modulo;
    return res;
}

inline int_mod operator*(const int_mod &a, const int_mod &b)
{
    int_mod res;

    res.val = (castformorebits(a.val) * b.val) % int_mod::modulo;

    return res;
}

inline int_mod operator/(const int_mod &a, const int_mod &b)
{
    // Assume modulo is prime
    int32 inverse = fast_exponential(b.val, int_mod::modulo-2, int_mod::modulo);

    return a * inverse;
}

inline void read(int_mod &a)
{
    scan("%" SCNd32, &a.val);
    a.val %= int_mod::modulo;
}

inline void write(const int_mod &b)
{
    printf("%" PRId32 " ", b.val);
}


inline void read(int32& val)
{
    scan("%" SCNd32, &val);
}

inline void read(int64& val)
{
    scan("%" SCNd64, &val);
}

inline void read(double& val)
{
    scan("%lf", &val);
}

inline void read(string& val, int length = 1e6)
{
    char tmp[length+1];

    scan("%s", tmp);

    val = tmp;
}

template <class S, class T>
inline void read(S& a, T& b)
{
    read(a);
    read(b);
}

template <class S>
inline void read(vector<S> &v, int n)
{
    v.resize(n);
    for (int i = 0; i < n; i++)
        read(v[i]);
}

template <class S, class T, class U>
inline void read(S& a, T& b, U& c)
{
    read(a);
    read(b);
    read(c);
}

template <class S, class T, class U, class V>
inline void read(S& a, T& b, U& c, V& d)
{
    read(a);
    read(b);
    read(c);
    read(d);
}

template <class S, class T, class U, class V, class W>
inline void read(S& a, T& b, U& c, V& d, W& e)
{
    read(a);
    read(b);
    read(c);
    read(d);
    read(e);
}

inline void write(int32 val)
{
    printf("%" PRId32 " ", val);
}

inline void write(int64 val)
{
    printf("%" PRId64 " ", val);
}

inline void write(double val)
{
    printf("%lf ", val);
}

inline void write(const string& val)
{
    printf("%s ", val.c_str());
}

template<class S>
inline void write(const vector<S>& val)
{
    for (S el : val)
        write(el);
}

template<class S>
inline void writeln(const S& a)
{
    write(a);
    printf("\n");
}

template<class S, class T>
inline void writeln(const S& a, const T& b)
{
    write(a);
    write(b);
    printf("\n");
}

template<class S, class T, class U>
inline void writeln(const S& a, const T& b, const U& c)
{
    write(a);
    write(b);
    write(c);
    printf("\n");
}

template<class S, class T, class U, class V>
inline void writeln(const S& a, const T& b, const U& c, const V& d)
{
    write(a);
    write(b);
    write(c);
    write(d);
    printf("\n");
}

template<class S, class T, class U, class V, class W>
inline void writeln(const S& a, const T& b, const U& c, const V& d, const W& e)
{
    write(a);
    write(b);
    write(c);
    write(d);
    write(e);
    printf("\n");
}

#ifdef PCL_DEBUG
    #define DBG_RED "\033[1;31m"
    #define DBG_YELLOW "\033[1;33m"
    #define DBG_BLUE "\033[1;34m"
    #define DBG_NC "\033[0m"

    #define debug(var) { printf("%s%s%s = ", DBG_RED, #var, DBG_NC); writeln(var); }
    #define break_point(str) { printf("%s%s%s\n", DBG_YELLOW, str, DBG_NC); }
#else
    #define debug(...)
    #define break_point(...)
#endif

bool is_bipartite(int v, vector<vector<int>> &graph, vector<int> &color, int c)
{
    color[v] = c;

    for (int u : graph[v])
    {
        if (color[u] == c)
            return false;
        if (color[u] == 0 and not is_bipartite(u, graph, color, 3 - c))
            return false;
    }

    return true;
}

int dfs(int v, vector<vector<int>> &graph, vector<bool> &visited)
{
    int Size = 1;

    visited[v] = true;
    for (int u : graph[v])
    {
        if (!visited[u])
        {
            Size += dfs(u, graph, visited);
        }
    }
    return Size;
}

pair<pair<int, int>, pair<int, int>> count_bipartite(int v, vector<vector<int>> &graph, vector<int> &start, vector<bool> &visited)
{
    pair<pair<int, int>, pair<int, int>> p = {{0, 0}, {0, 0}};

    visited[v] = true;

    if (start[v] == 0)
        p.first.first++;
    else
        p.first.second++;

    for (int u : graph[v])
    {
        if (!visited[u])
        {
            auto q = count_bipartite(u, graph, start, visited);
            p.first.first += q.second.first;
            p.first.second += q.second.second;
            p.second.first += q.first.first;
            p.second.second += q.first.second;
        }
    }

    return p;
}

int main()
{
    int_mod::modulo = 1'000'000'007;

    int n, m;
    vector<int> start;
    vector<vector<int>> graph;
    vector<bool> visited;
    vector<bool> visited2;
    vector<int> color;

    read(n, m);
    read(start, n);

    graph.resize(n);

    for (int i = 0; i < m; i++)
    {
        int a, b;
        read(a, b);
        a--;
        b--;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }

    visited.resize(n, false);
    visited2.resize(n, false);
    color.resize(n, 0);

    int_mod result = 1;

    vector<int_mod> silnie(n + 1, 1);

    for (int i = 1; i <= n; i++)
        silnie[i] = silnie[i - 1] * i;

    for (int u = 0; u < n; u++)
        if (!visited[u])
        {
            int Size = dfs(u, graph, visited);

            if (is_bipartite(u, graph, color, 1))
            {
                auto p = count_bipartite(u, graph, start, visited2);

                int l0 = p.first.first;
                int l1 = p.first.second;
                int r0 = p.second.first;
                int r1 = p.second.second;
//writeln(l0, l1, r0, r1);
                int_mod r = 0;

                for (int i = 0; i <= l0 + l1; i++)
                {

                    int j = r1 + i - l1;
//writeln(i, j);
                    if (0 <= j and j <= r1 + r0)
                    {
                        int_mod a = silnie[l0 + l1] / (silnie[i] * silnie[l0 + l1 - i]);
                        int_mod b = silnie[r0 + r1] / (silnie[j] * silnie[r0 + r1 - j]);

                        r += a * b;
                    }
                }

                result *= r;
//writeln("bipartite", r);
            }
            else
            {
                for (int i = 1; i < Size; i++)
                    result *= 2;
//writeln("not bipartite", Size);
            }
        }
    
    writeln(result);

    return 0;
}