import sys
from collections import Counter
n, m, k = map(int, sys.stdin.readline().strip().split())
mod = 998244353
nums = Counter(map(int, sys.stdin.readline().strip().split()))
for _ in range(m):
X, Y = map(int, sys.stdin.readline().strip().split())
nums = {ke + X: va % mod for ke, va in nums.items() if ke + X > 0}
for ke, va in nums.copy().items():
if ke > k:
del nums[ke]
nums[1] = (nums.get(1, 0) + (ke - k) * va) % mod
nums[k] = (nums.get(k, 0) + va) % mod
if Y != 0:
nums[Y] = (nums.get(Y, 0) + 1) % mod
print(sum(ke * va % mod for ke, va in nums.items()) % mod)