import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.ArrayList; import java.util.Arrays; import java.util.InputMismatchException; import java.util.NoSuchElementException; public class Main { static PrintWriter out; static InputReader ir; static void solve() { int n = ir.nextInt(); int m = ir.nextInt(); char[] s = ir.next().toCharArray(); Graph[] g = new Graph[n]; for (int i = 0; i < n; i++) { g[i] = new Graph(); } for (int i = 0; i < m; i++) { int u = ir.nextInt() - 1; int v = ir.nextInt() - 1; g[u].add(new int[] { v }); g[v].add(new int[] { u }); } long[] dp = new long[n]; char[] t = new char[] { 'P', 'D', 'C', 'A' }; for (int i = 0; i < n; i++) { if (s[i] == 'A') dp[i] = 1; } long res = 0; for (int i = 2; i >= 0; i--) { for (int j = 0; j < n; j++) { if (s[j] != t[i]) continue; for (int[] to : g[j]) { if (s[to[0]] == t[i + 1]) { dp[j] = add(dp[j], dp[to[0]]); } } if (i == 0) res = add(res, dp[j]); } } out.println(res); } static class Graph extends ArrayList { } static long mod = (long) 1e9 + 7; static long add(long a, long b) { return (a + b) % mod; } static long sub(long a, long b) { long d = a - b; while (d < 0) d += mod; return d; } static long mul(long a, long b) { return a * b % mod; } static long div(long a, long b) { return a * mod_inverse(b) % mod; } public static long[] fact(int n) { long[] ret = new long[n + 1]; ret[0] = 1 % mod; for (int i = 1; i <= n; i++) { ret[i] = mul(ret[i - 1], i); } return ret; } private static long[] factInv(int n) { long[] ret = new long[n + 1]; ret[0] = 1; for (int i = 1; i <= n; i++) { ret[i] = div(ret[i - 1], i); } return ret; } public static long comb(int n, int m, long[] fact, long[] factInv) { long ret = fact[n]; ret = mul(ret, factInv[m]); ret = mul(ret, factInv[n - m]); return ret; } public static long[][] stirling(int n) { long[][] ret = new long[n + 1][n + 1]; ret[0][0] = 1; for (int i = 1; i <= n; i++) for (int j = 1; j <= i; j++) ret[i][j] = add(ret[i - 1][j - 1], mul(ret[i - 1][j], j)); return ret; } public static long mod_inverse(long a) { long[] ret = extgcd(a, mod); return add(mod, ret[0] % mod); } private static long[] extgcd(long a, long b) { long[] ret = new long[3]; ret[2] = _extgcd(a, b, ret); return ret; } private static long _extgcd(long a, long b, long[] x) { long g = a; x[0] = 1; x[1] = 0; if (b != 0) { g = _extgcd(b, a % b, x); long temp = x[0]; x[0] = x[1]; x[1] = temp; x[1] -= (a / b) * x[0]; } return g; } static long modpow(long a, long n) { long res = 1; while (n > 0) { if ((n & 1) != 0) res = res * a % mod; a = a * a % mod; n >>= 1; } return res; } public static void main(String[] args) { ir = new InputReader(System.in); out = new PrintWriter(System.out); solve(); out.flush(); } static class InputReader { private InputStream in; private byte[] buffer = new byte[1024]; private int curbuf; private int lenbuf; public InputReader(InputStream in) { this.in = in; this.curbuf = this.lenbuf = 0; } public boolean hasNextByte() { if (curbuf >= lenbuf) { curbuf = 0; try { lenbuf = in.read(buffer); } catch (IOException e) { throw new InputMismatchException(); } if (lenbuf <= 0) return false; } return true; } private int readByte() { if (hasNextByte()) return buffer[curbuf++]; else return -1; } private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); } private void skip() { while (hasNextByte() && isSpaceChar(buffer[curbuf])) curbuf++; } public boolean hasNext() { skip(); return hasNextByte(); } public String next() { if (!hasNext()) throw new NoSuchElementException(); StringBuilder sb = new StringBuilder(); int b = readByte(); while (!isSpaceChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public int nextInt() { if (!hasNext()) throw new NoSuchElementException(); int c = readByte(); while (isSpaceChar(c)) c = readByte(); boolean minus = false; if (c == '-') { minus = true; c = readByte(); } int res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res = res * 10 + c - '0'; c = readByte(); } while (!isSpaceChar(c)); return (minus) ? -res : res; } public long nextLong() { if (!hasNext()) throw new NoSuchElementException(); int c = readByte(); while (isSpaceChar(c)) c = readByte(); boolean minus = false; if (c == '-') { minus = true; c = readByte(); } long res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res = res * 10 + c - '0'; c = readByte(); } while (!isSpaceChar(c)); return (minus) ? -res : res; } public double nextDouble() { return Double.parseDouble(next()); } public int[] nextIntArray(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) a[i] = nextInt(); return a; } public long[] nextLongArray(int n) { long[] a = new long[n]; for (int i = 0; i < n; i++) a[i] = nextLong(); return a; } public char[][] nextCharMap(int n, int m) { char[][] map = new char[n][m]; for (int i = 0; i < n; i++) map[i] = next().toCharArray(); return map; } } static void tr(Object... o) { out.println(Arrays.deepToString(o)); } }