MOD = 998_244_353
U = 10**5
INF = float("INF")
N = int(input())
A = list(map(int, input().split()))
A.append(0)

dp = [0]*(U+1)
dp[0] = 1
for i in range(N):
   dc = A[i] - A[i-1]
   ndp = [0]*(U+1)
   dc = max(0, dc)
   wa = 0
   for nc in range(U+1):
      if nc-dc < 0:
         continue
      wa += dp[nc-dc]
      ndp[nc] += wa
      ndp[nc] %= MOD
   dp = ndp

ans = sum(dp)
ans %= MOD
print(ans)