MOD = 998244353
N = int(input())
A = list(map(int, input().split()))
B = [0] * N
C = [0] * N

for i in range(1, N):
    B[i] = B[i - 1]
    if A[i - 1] > A[i]:
        B[i] += A[i - 1] - A[i]
    C[i] = B[i] + A[i]

N2 = 10 ** 5
X = [0] * (N2 + 1)
X[0] = 1
maxc = 0
for i in reversed(range(N)):
    X2 = [0] * (N2 + 1)
    # print(i,A[i],B[i],A[i]+B[i],N2-maxc+1)
    maxc = max(maxc, C[i])
    for j in range(N2 - maxc + 1):
        X2[j] = X2[j - 1] + X[j]
        X2[j] %= MOD
    X = X2
print(sum(X) % MOD)