# import sys; input = sys.stdin.buffer.readline
# sys.setrecursionlimit(10**7)
from collections import defaultdict
from collections import deque
con = 10 ** 9 + 7; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

class Graph(object):
	def __init__(self):
		self.graph = defaultdict(list)

	def __len__(self):
		return len(self.graph)

	def add_edge(self, a, b):
		self.graph[a].append(b)

#処理内容
def main():
	N, M = getlist()
	S = input()
	G = Graph()
	DP = [0] * N
	for i in range(N):
		if S[i] == "P":
			DP[i] = 1

	for i in range(M):
		a, b = getlist()
		a -= 1; b -= 1
		if (S[a] == "P" and S[b] =="D") or (S[a] == "D" and S[b] =="C") or (S[a] == "C" and S[b] =="A"):
			G.add_edge(a, b)
		if (S[a] == "A" and S[b] =="C") or (S[a] == "C" and S[b] =="D") or (S[a] == "D" and S[b] =="P"):
			G.add_edge(b, a)

	for i in range(N):
		if S[i] == "P":
			for v in G.graph[i]:
				DP[v] += DP[i]

	for i in range(N):
		if S[i] == "D":
			for v in G.graph[i]:
				DP[v] += DP[i]

	for i in range(N):
		if S[i] == "C":
			for v in G.graph[i]:
				DP[v] += DP[i]

	ans = 0
	for i in range(N):
		if S[i] == "A":
			ans += DP[i]

	print(ans % con)

if __name__ == '__main__':
	main()