import java.io.*; import java.util.*; public class Main_yukicoder762 { private static Scanner sc; private static Printer pr; private static void solve() { final int MOD = 1_000_000_007; int n = sc.nextInt(); int m = sc.nextInt(); char[] s = sc.next().toCharArray(); List> edges = new ArrayList<>(n); for (int i = 0; i < n; i++) { edges.add(new ArrayList<>()); } for (int i = 0; i < m; i++) { int u = sc.nextInt() - 1; int v = sc.nextInt() - 1; edges.get(u).add(v); edges.get(v).add(u); } int[] cnt = new int[n]; for (int i = 0; i < n; i++) { if (s[i] == 'A') { cnt[i] = 1; } } for (int i = 0; i < n; i++) { if (s[i] == 'C') { for (int e : edges.get(i)) { if (s[e] == 'A') { cnt[i] += cnt[e]; cnt[i] %= MOD; } } } } for (int i = 0; i < n; i++) { if (s[i] == 'D') { for (int e : edges.get(i)) { if (s[e] == 'C') { cnt[i] += cnt[e]; cnt[i] %= MOD; } } } } int ans = 0; for (int i = 0; i < n; i++) { if (s[i] == 'P') { for (int e : edges.get(i)) { if (s[e] == 'D') { cnt[i] += cnt[e]; cnt[i] %= MOD; } } ans += cnt[i]; ans %= MOD; } } pr.println(ans); } // --------------------------------------------------- public static void main(String[] args) { sc = new Scanner(System.in); pr = new Printer(System.out); solve(); pr.close(); sc.close(); } static class Scanner { BufferedReader br; Scanner (InputStream in) { br = new BufferedReader(new InputStreamReader(in)); } private boolean isPrintable(int ch) { return ch >= '!' && ch <= '~'; } private boolean isCRLF(int ch) { return ch == '\n' || ch == '\r' || ch == -1; } private int nextPrintable() { try { int ch; while (!isPrintable(ch = br.read())) { if (ch == -1) { throw new NoSuchElementException(); } } return ch; } catch (IOException e) { throw new NoSuchElementException(); } } String next() { try { int ch = nextPrintable(); StringBuilder sb = new StringBuilder(); do { sb.appendCodePoint(ch); } while (isPrintable(ch = br.read())); return sb.toString(); } catch (IOException e) { throw new NoSuchElementException(); } } int nextInt() { try { // parseInt from Integer.parseInt() boolean negative = false; int res = 0; int limit = -Integer.MAX_VALUE; int radix = 10; int fc = nextPrintable(); if (fc < '0') { if (fc == '-') { negative = true; limit = Integer.MIN_VALUE; } else if (fc != '+') { throw new NumberFormatException(); } fc = br.read(); } int multmin = limit / radix; int ch = fc; do { int digit = ch - '0'; if (digit < 0 || digit >= radix) { throw new NumberFormatException(); } if (res < multmin) { throw new NumberFormatException(); } res *= radix; if (res < limit + digit) { throw new NumberFormatException(); } res -= digit; } while (isPrintable(ch = br.read())); return negative ? res : -res; } catch (IOException e) { throw new NoSuchElementException(); } } long nextLong() { try { // parseLong from Long.parseLong() boolean negative = false; long res = 0; long limit = -Long.MAX_VALUE; int radix = 10; int fc = nextPrintable(); if (fc < '0') { if (fc == '-') { negative = true; limit = Long.MIN_VALUE; } else if (fc != '+') { throw new NumberFormatException(); } fc = br.read(); } long multmin = limit / radix; int ch = fc; do { int digit = ch - '0'; if (digit < 0 || digit >= radix) { throw new NumberFormatException(); } if (res < multmin) { throw new NumberFormatException(); } res *= radix; if (res < limit + digit) { throw new NumberFormatException(); } res -= digit; } while (isPrintable(ch = br.read())); return negative ? res : -res; } catch (IOException e) { throw new NoSuchElementException(); } } float nextFloat() { return Float.parseFloat(next()); } double nextDouble() { return Double.parseDouble(next()); } String nextLine() { try { int ch; while (isCRLF(ch = br.read())) { if (ch == -1) { throw new NoSuchElementException(); } } StringBuilder sb = new StringBuilder(); do { sb.appendCodePoint(ch); } while (!isCRLF(ch = br.read())); return sb.toString(); } catch (IOException e) { throw new NoSuchElementException(); } } void close() { try { br.close(); } catch (IOException e) { // throw new NoSuchElementException(); } } } static class Printer extends PrintWriter { Printer(OutputStream out) { super(out); } } }