#include <iostream>
#include <vector>

class Node {
    public:
    int num;
    char s;
    std::vector<int> node_nums;
    Node(int num, char s) : num(num), s(s) {}
    int append(int n) {
        node_nums.push_back(n);
        return n;
    }


};

std::vector<Node> nodes;
void search_pdca(Node& node, int count, int& n) {
    std::string pdca = "PDCA";
    if (node.s == pdca[count]) {
        if (count == 3) {
            n += 1;
            return;
        }
        for (int i = 0; i < node.node_nums.size(); i++) {
            search_pdca(nodes[node.node_nums[i]], count + 1, n);
        }
    }
}

int main() {
    std::string pdca = "PDCA";
    int n, m, q, count;
    count = 0;
    std::string s;
    std::cin >> n >> m;
    std::cin >> s;
    for (int i = 0; i < n; i++) {
        nodes.push_back(Node(i, s[i]));
    }
    int u, v;
    for (int i = 0; i < m; i++) {
        std::cin >> u >> v;
        u -= 1;
        v -= 1;
        std::string m = {nodes[u].s, nodes[v].s};
        if (m == "PD" || m == "DC" || m == "CA") {
            nodes[u].append(v);
            nodes[v].append(u);
        }
    }
    for (int i = 0; i < nodes.size(); i++) {
        search_pdca(nodes[i], 0, count);
    }
    std::cout << count % 1000000007 << std::endl;
};