1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
#include <iostream>
#include <vector>
#include <queue>
#include <math.h>

using namespace std;

const long long MOD = 1000000007;
queue<int> q;
queue<int> q2;
int counter=0;
bool dwud = 1;
bool odw[200007];
long long two[400008];
vector<int> v[200007];
vector< pair<int, int> > graph[400007];
void bfs(int pp, int a) {
    odw[pp] = true;
    graph[a].push_back({pp, pp});
    q2.push(pp);
    while (!q2.empty()) {
        int x = q2.front();
        q2.pop();
        for (int i = 0; i < v[x].size(); i ++)
            if(odw[v[x][i]] == false) {
                odw[v[x][i]] = true;
                graph[a].push_back({x, v[x][i]});
                q2.push(v[x][i]);
            }
    }
}
bool isBipartite(int pp, vector<int>& color) {
    color[pp] = 0;
    queue<int> q;
    q.push(pp);
    while (!q.empty()) {
        int x = q.front();
        q.pop();
        for (int i = 0; i < v[x].size(); i++) {
            if (color[v[x][i]] == -1) {
                color[v[x][i]] = 1 - color[x];
                q.push(v[x][i]);
            } else if (color[v[x][i]] == color[x]) {
                return false;
            }
        }
    }
    return true;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int n, m;
    cin >> n >> m;
    vector<int> initial_state(n+1);
    for (int i = 1; i <= n; ++i) {
        cin >> initial_state[i];
    }
    for (int i = 0; i < m; ++i) {
        int ai, bi;
        cin >> ai >> bi;
        v[ai].push_back(bi);
        v[bi].push_back(ai);
    }
    int odwa=0;
    for(int i=1;i<=n;i++){
        if(!odw[i]){
            bfs(i, counter);
        }
        odwa+=graph[counter].size();
        counter++;
        if(odwa == n){
            break;
        }
    }
    long long answer=1;
    two[0]=1;
    for(int i=1;i<400002;i++){
        answer *= 2LL;
        answer %= MOD;
        two[i] = answer;
    }
    answer = 1;
    for(int i=0;i<counter;i++){
        bool flag = false;
        if(graph[i].size()>1){
            vector<int> col(n+1, -1);
            dwud = isBipartite(graph[i][0].first, col);
        }
        for(int j=1;j<graph[i].size();j++){
            if(initial_state[graph[i][j].first] == initial_state[graph[i][j].second]){
                flag = true;
                break;
            }
        }
        if(flag){
            if(graph[i].size() == 2){
                answer *= 2;
            }
            else if(dwud){
                answer *= (graph[i].size()*graph[i].size() - 2*graph[i].size()) % MOD;
            }
            else {
                answer *= two[graph[i].size()-1] % MOD;
            }
        }
    }
    cout<<answer<<endl;
    return 0;
}