import std.algorithm, std.container, std.conv, std.math, std.range, std.typecons, std.stdio, std.string;

auto rdsp(){return readln.splitter;}
void pick(R,T)(ref R r,ref T t){t=r.front.to!T;r.popFront;}
void readV(T...)(ref T t){auto r=rdsp;foreach(ref v;t)pick(r,v);}

const mod = 10^^9+7;
alias mint = FactorRing!mod;

void main()
{
  int n, m; readV(n, m);
  string s; readV(s);

  auto g = Graph!int(n);
  foreach (_; 0..m) {
    int u, v; readV(u, v); --u; --v;
    g.addEdgeB(u, v);
  }

  auto p = new mint[](n), d = new mint[](n), c = new mint[](n), a = new mint[](n);

  foreach (i; 0..n)
    if (s[i] == 'P')
      p[i] = 1;

  foreach (i; 0..n)
    if (s[i] == 'P')
      foreach (j; g[i])
        if (s[j] == 'D')
          d[j] += p[i];

  foreach (i; 0..n)
    if (s[i] == 'D')
      foreach (j; g[i])
        if (s[j] == 'C')
          c[j] += d[i];

  foreach (i; 0..n)
    if (s[i] == 'C')
      foreach (j; g[i])
        if (s[j] == 'A')
          a[j] += c[i];

  writeln(a.sum);
}

struct Graph(N = int)
{
  alias Node = N;
  Node n;
  Node[][] g;
  alias g this;
  this(Node n) { this.n = n; g = new Node[][](n); }
  void addEdge(Node u, Node v) { g[u] ~= v; }
  void addEdgeB(Node u, Node v) { g[u] ~= v; g[v] ~= u; }
}

struct FactorRing(int m, bool pos = false)
{
  version(BigEndian) union { long vl; struct { int vi2; int vi; } } else union { long vl; int vi; }
  alias FR = FactorRing!(m, pos);
  @property static init() { return FR(0); }
  @property int value() { return vi; }
  @property void value(int v) { vi = mod(v); }
  alias value this;

  this(int v) { vi = v; }
  this(int v, bool runMod) { vi = runMod ? mod(v) : v; }
  this(long v) { vi = mod(v); }

  ref auto opAssign(int v) { vi = v; return this; }

  pure auto mod(int v) const { static if (pos) return v%m; else return (v%m+m)%m; }
  pure auto mod(long v) const { static if (pos) return cast(int)(v%m); else return cast(int)((v%m+m)%m); }

  static if (!pos) pure ref auto opUnary(string op: "-")() { return FR(mod(-vi)); }

  static if (m < int.max / 2) {
    pure ref auto opBinary(string op)(int r) if (op == "+" || op == "-") { return FR(mod(mixin("vi"~op~"r"))); }
    ref auto opOpAssign(string op)(int r) if (op == "+" || op == "-") { vi = mod(mixin("vi"~op~"r")); return this; }
  } else {
    pure ref auto opBinary(string op)(int r) if (op == "+" || op == "-") { return FR(mod(mixin("vl"~op~"r"))); }
    ref auto opOpAssign(string op)(int r) if (op == "+" || op == "-") { vi = mod(mixin("vl"~op~"r")); return this; }
  }
  pure ref auto opBinary(string op: "*")(int r) { return FR(mod(vl*r)); }
  ref auto opOpAssign(string op: "*")(int r) { vi = mod(vl*r); return this; }

  pure ref auto opBinary(string op)(ref FR r) if (op == "+" || op == "-" || op == "*") { return opBinary!op(r.vi); }
  ref auto opOpAssign(string op)(ref FR r) if (op == "+" || op == "-" || op == "*") { return opOpAssign!op(r.vi); }
}