#include<bits/stdc++.h>
typedef long long ll;
using namespace std;
int n,q;
const ll mod=998244353;
struct node{
	int l,r,lazy,cnt;
	ll sum;
}Tree[800005];
char s[200005];
int a[200005];
void pushup(int p){
	Tree[p].sum=(Tree[p*2].sum+Tree[p*2+1].sum)%mod;
	Tree[p].cnt=Tree[p*2].cnt+Tree[p*2+1].cnt;
}
void ztree(int p,int l,int r){
	Tree[p].l=l,Tree[p].r=r;
	Tree[p].lazy=0;
	if(l==r){
		Tree[p].cnt=a[l];
		Tree[p].sum=1ll*a[l]*l;
		return;
	}
	int mid=l+r>>1;
	ztree(p*2,l,mid);
	ztree(p*2+1,mid+1,r);
	pushup(p);
}
ll Gs(int l,int r){
	ll a=1ll*(l+r)*(r-l+1)/2;
	return a%mod;
}
void pushdown(int p){
	if(!Tree[p].lazy)return;
	Tree[p*2].lazy^=1;
	Tree[p*2].cnt=(Tree[p*2].r-Tree[p*2].l+1)-Tree[p*2].cnt;
	Tree[p*2].sum=(Gs(Tree[p*2].l,Tree[p*2].r)-Tree[p*2].sum+mod)%mod;
	Tree[p*2+1].lazy^=1;
	Tree[p*2+1].cnt=(Tree[p*2+1].r-Tree[p*2+1].l+1)-Tree[p*2+1].cnt;
	Tree[p*2+1].sum=(Gs(Tree[p*2+1].l,Tree[p*2+1].r)-Tree[p*2+1].sum+mod)%mod;
	Tree[p].lazy=0;
}
void update(int p,int l,int r){
	if(l<=Tree[p].l&&Tree[p].r<=r){
		Tree[p].lazy^=1;
		Tree[p].cnt=(Tree[p].r-Tree[p].l+1)-Tree[p].cnt;
		Tree[p].sum=(Gs(Tree[p].l,Tree[p].r)-Tree[p].sum+mod)%mod;
		return;
	}
	pushdown(p);
	int mid=Tree[p].l+Tree[p].r>>1;
	if(l<=mid)update(p*2,l,r);
	if(r>mid)update(p*2+1,l,r);
	pushup(p);
}
ll Getsum(int p,int l,int r){
	if(l<=Tree[p].l&&Tree[p].r<=r){
		return Tree[p].sum;
	}
	pushdown(p);
	int mid=Tree[p].l+Tree[p].r>>1;
	ll c=0;
	if(l<=mid)c=Getsum(p*2,l,r);
	if(r>mid)c=(c+Getsum(p*2+1,l,r))%mod;
	return c;
}
int main(){
	scanf("%d%d",&n,&q);
	scanf("%s",s+1);
	for(int i=1;i<=n;i++)a[i]=s[i]-'0';
	ztree(1,1,n);
	while(q--){
		int l,r;
		scanf("%d%d",&l,&r);
		update(1,l,r);
		int p=Tree[1].cnt;
		ll ans=0;
		if(p!=n)ans+=Getsum(1,p+1,n);
		ans-=(Gs(1,p)-Getsum(1,1,p)+mod)%mod;
		printf("%lld\n",(ans*2ll+p+mod)%mod);
	}
	return 0;
}