#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic pop
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;
using mint = modint998244353;

constexpr int M = 200010;
mint pow2[M], powinv2[M];

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  const mint inv2 = mint(2).inv();
  pow2[0] = powinv2[0] = 1;
  rep(i, M - 1) {
    pow2[i + 1] = pow2[i] * 2;
    powinv2[i + 1] = powinv2[i] * inv2;
  }
  int n, q;
  cin >> n >> q;
  VI a(n);
  rep(i, n) cin >> a[i];
  vector<mint> s(n + 1);
  rep(i, n) s[i + 1] = s[i] + a[i] * pow2[i];
  VI last_le(n);
  rep(i, n - 1) last_le[i + 1] = a[i] >= a[i + 1] ? i + 1 : last_le[i];
  while(q--) {
    int l, r;
    cin >> l >> r;
    l--;
    chmax(l, last_le[r - 1]);
    mint ans = a[l];
    ans += (s[r] - s[l + 1]) * powinv2[l + 1];
    cout << ans.val() << '\n';
  }
}