import sys
sys.setrecursionlimit((1<<19)-1)
#import pypyjit
#pypyjit.set_param('max_unroll_recursion=-1')
input=sys.stdin.buffer.readline

MOD=998244353
sc=100000
N=int(input())
A=[0]+list(map(int,input().split()))
dp=[0]*(sc+1)
dp[0]=1
for i in range(N):
    ndp=[0]*(sc+1)
    ans=0
    for j in range(sc+1):
        if A[i+1]+j>sc:
            break
        if A[i]<=A[i+1]:
            ans+=dp[j]
        else:
            if j-(A[i]-A[i+1])>=0:
                ans+=dp[j-(A[i]-A[i+1])]
        ans%=MOD
        ndp[j]=ans
    dp=ndp
print(sum(dp)%MOD)