n=int(input())
a=list(map(int,input().split()))
q=[0]*n
M=998244353
d={}
c={}
for i in range(n):
	if a[i]-1 in d:
		q[i]=(d[a[i]-1]+c[a[i]-1])%M
	if a[i] not in d:
		d[a[i]]=0
		c[a[i]]=0
	d[a[i]]+=q[i]
	c[a[i]]+=1
print(sum(q)%M)