import sys

# sys.setrecursionlimit(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
inf = (1 << 63)-1
# inf = (1 << 31)-1
# md = 10**9+7
md = 998244353

class RollingHash:
    def __init__(self, target):
        self.BASE = 2
        self.MOD = md
        self.N = len(target)
        self.table = [0]
        self.power = [1]
        for c in target:
            self.table += [self._mod(self.table[-1]*self.BASE)+c]
            self.power += [self._mod(self.power[-1]*self.BASE)]

    def _mod(self, a):
        return a%self.MOD

    def hash_lr(self, l, r):
        return self._mod(self.table[r]-self._mod(self.table[l]*self.power[r-l]))

from bisect import bisect_left

n, q = LI()
aa = LI()

ii = [0]
for i in range(n-1):
    if aa[i] >= aa[i+1]: ii.append(i+1)

rh = RollingHash(aa[::-1])

for _ in range(q):
    l, r = LI()
    l -= 1
    l = max(l, ii[bisect_left(ii, r)-1])
    ans = rh.hash_lr(n-r, n-(l+1))+aa[l]
    print(ans%md)