J=lambda:map(int,input().split())
N,P,C=J()
A=[[]]
for a in J():
	if a:A[-1]+=[a]
	else:A+=[[]]
a=(C<1)*N*(N+1)//2
for v in A:
	c={}
	if C:
		t=1
		for w in v:
			u,t=t*C%P,w*t%P
			c[u]=c[u]+1if u in c else 1
			a+=c[t]if t in c else 0
	else:
		t=len(v)
		a-=t*(t+1)//2
print(a)