N=int(input())
A=list(map(int,input().split()))
'''
dp[~番目まで見て][仮のスコアが--]
'''
p=998244353
lim=10**5
dp=[[0 for _ in range(lim+1)] for _ in range(N)]
dp[0]=[1 for _ in range(lim+1)]
for i in range(N-1):
    for j in range(lim+1):
        if j+A[i]>lim:
            continue
        move=max(j+A[i]-A[i+1],j)
        if j<=lim:
            dp[i+1][move]+=dp[i][j]
            dp[i+1][move]%=p
    for j in range(1,lim+1):
        dp[i+1][j]+=dp[i+1][j-1]
        dp[i+1][j]%=p
ans=0
for j in range(lim+1):
    if j+A[-1]>lim:
        break
    ans+=dp[-1][j]
    ans%=p
print(ans)