#include <bits/stdc++.h>
using namespace std;

#if defined(_WIN32) || defined(_WIN64)
#define getchar_unlocked _getchar_nolock
#define putchar_unlocked _putchar_nolock
#elif defined(__GNUC__)
#else
#define getchar_unlocked getchar
#define putchar_unlocked putchar
#endif
namespace {
#define isvisiblechar(c) (0x21<=(c)&&(c)<=0x7E)
    class MaiScanner {
    public:
        template<typename T> void input_integer(T& var) noexcept {
            var = 0; T sign = 1;
            int cc = getchar_unlocked();
            for (; cc<'0' || '9'<cc; cc = getchar_unlocked())
                if (cc == '-') sign = -1;
            for (; '0' <= cc && cc <= '9'; cc = getchar_unlocked())
                var = (var << 3) + (var << 1) + cc - '0';
            var = var * sign;
        }
        inline int c() noexcept { return getchar_unlocked(); }
        inline MaiScanner& operator>>(int& var) noexcept { input_integer<int>(var); return *this; }
        inline MaiScanner& operator>>(long long& var) noexcept { input_integer<long long>(var); return *this; }
        inline MaiScanner& operator>>(string& var) {
            int cc = getchar_unlocked();
            for (; !isvisiblechar(cc); cc = getchar_unlocked());
            for (; isvisiblechar(cc); cc = getchar_unlocked())
                var.push_back(cc);
            return *this;
        }
        template<typename IT> inline void in(IT begin, IT end) { for (auto it = begin; it != end; ++it) *this >> *it; }
    };
    class MaiPrinter {
    public:
        template<typename T>
        void output_integer(T var) noexcept {
            if (var == 0) { putchar_unlocked('0'); return; }
            if (var < 0)
                putchar_unlocked('-'),
                var = -var;
            char stack[32]; int stack_p = 0;
            while (var)
                stack[stack_p++] = '0' + (var % 10),
                var /= 10;
            while (stack_p)
                putchar_unlocked(stack[--stack_p]);
        }
        inline MaiPrinter& operator<<(char c) noexcept { putchar_unlocked(c); return *this; }
        inline MaiPrinter& operator<<(int var) noexcept { output_integer<int>(var); return *this; }
        inline MaiPrinter& operator<<(long long var) noexcept { output_integer<long long>(var); return *this; }
        inline MaiPrinter& operator<<(char* str_p) noexcept { while (*str_p) putchar_unlocked(*(str_p++)); return *this; }
        inline MaiPrinter& operator<<(const string& str) {
            const char* p = str.c_str();
            const char* l = p + str.size();
            while (p < l) putchar_unlocked(*p++);
            return *this;
        }
        template<typename IT> void join(IT begin, IT end, char sep = ' ') { for (bool b = 0; begin != end; ++begin, b = 1) b ? *this << sep << *begin : *this <<* begin; }
    };
}
MaiScanner scanner;
MaiPrinter printer;


// =============================================================================
using ll = long long;
const ll MD = 1e9+7;


int N, M;
string label;
int dp[100010];
vector<pair<int, int> > edge_pd, edge_dc, edge_ca;

int main() {
    scanner >> N >> M >> label;
    edge_pd.reserve(M);
    edge_dc.reserve(M);
    edge_ca.reserve(M);
    for (int _ = M-1; 0 <= _; --_) {
        int a, b;
        char ca, cb;
        scanner >> a >> b;
        --a; --b;
        if (label[a] < label[b]) swap(a, b); // note: [A,C,D,P]を降順に並べるとPDCA
        
        ca = label[a];
        cb = label[b];
        
        if (ca == 'P' && cb == 'D') {
            edge_pd.emplace_back(a, b);
            dp[a] = 1;
        }
        else if (ca == 'D' && cb == 'C') {
            edge_dc.emplace_back(a, b);
        }
        else if (ca == 'C' && cb == 'A') {
            edge_ca.emplace_back(a, b);
        }
    }
    for (auto edge : edge_pd) {
        dp[edge.second] = (dp[edge.second] + dp[edge.first]) % MD;
    }
    for (auto edge : edge_dc) {
        dp[edge.second] = (dp[edge.second] + dp[edge.first]) % MD;
    }
    int answer = 0;
    for (auto edge : edge_ca) {
        answer = (answer + dp[edge.first]) % MD;
    }
    cout << answer << endl;
    
    return 0;
}