#include <bits/stdc++.h>
using namespace std;

const int MAXN = 2e5+5;
using ll = long long;
const ll mod = 998244353;

int n,q;
string S;

pair<ll,ll> operator+(pair<ll,ll> a, pair<ll,ll> b)
{
    return {a.first + b.first, a.second + b.second};
}

struct SEG
{
    struct node
    {
        int l,r;
        ll cnt1, cnt1i;     //区间内1的数量，1的下标和
        bool flip;
    }t[MAXN<<2];

    #define ls (p<<1)
    #define rs ((p<<1)|1)

    void upd(int p)
    {
        t[p].cnt1 = (t[p].r - t[p].l + 1) - t[p].cnt1;
        t[p].cnt1i = 1ll * (t[p].l + t[p].r) * (t[p].r - t[p].l + 1) / 2 - t[p].cnt1i;
        t[p].flip ^= 1;
    }

    void pushup(int p)
    {
        t[p].cnt1 = t[ls].cnt1 + t[rs].cnt1;
        t[p].cnt1i = t[ls].cnt1i + t[rs].cnt1i;
    }

    void pushdown(int p)
    {
        if(t[p].flip)
        {
            upd(ls); upd(rs);
            t[p].flip = 0;
        }
    }

    void build(int p, int l, int r)
    {
        t[p].l = l; t[p].r = r; t[p].flip = 0;
        if(l == r)
        {
            if(S[l-1] == '1') t[p].cnt1 = 1, t[p].cnt1i = l;
            else t[p].cnt1 = t[p].cnt1i = 0;
            return;
        }
        int mid = (l+r)/2;
        build(ls, l, mid); build(rs, mid+1, r);
        pushup(p);
    }

    void update(int p, int L, int R)
    {
        if(L <= t[p].l && t[p].r <= R)
        {
            upd(p);
            return;
        }
        pushdown(p);
        int mid = (t[p].l + t[p].r) / 2;
        if(L <= mid) update(ls, L, R);
        if(R > mid) update(rs, L, R);
        pushup(p);
    }

    pair<ll,ll> query(int p, int L, int R)
    {
        if(L <= t[p].l && t[p].r <= R)
        {
            return {t[p].cnt1, t[p].cnt1i};
        }
        pushdown(p);
        int mid = (t[p].l + t[p].r) / 2;
        pair<ll,ll> ret = {0, 0};
        if(L <= mid) ret = ret + query(ls, L, R);
        if(R > mid) ret = ret + query(rs, L, R);
        return ret;
    }

}seg;

void solve()
{
    cin >> S;
    seg.build(1, 1, n);
    while(q--)
    {
        int l,r; cin >> l >> r;
        seg.update(1, l, r);
        int s = seg.query(1, 1, n).first;
        int val = seg.query(1, s, s).first;
        ll suma = ((1 <= s-1) ? 1ll * s * (s-1) / 2 - seg.query(1, 1, s-1).second : 0);
        ll sumb = ((s+1 <= n) ? seg.query(1, s+1, n).second : 0);
        ll ans = (val == 1 ? sumb - suma + s : sumb - suma - s);
        ans = ans % mod;
        //printf("s=%d, val=%d, suma=%lld, sumb=%lld, ans=%lld\n",s,val,suma,sumb,ans);
        cout << ans << endl;
    }
}

int main()
{
    while(cin >> n >> q)
    {
        solve();
    }
    return 0;
}