#include<bits/stdc++.h>
using namespace std;
#define ll long long
const ll maxn=200005;
const ll mod=998244353;
ll s[maxn+5],p[maxn+5];
ll qmksm(ll a,ll b){
    ll ans,i,j,k;
    ans=1;
    while(b){
        if(b&1) ans=ans*a%mod;
        a=a*a%mod;
        b>>=1;
    }
    return ans;
}
void init(){
    ll i,j,k;
    s[0]=1;
    for(i=1;i<=maxn;i++) s[i]=s[i-1]*i%mod;
    p[maxn]=qmksm(s[maxn],mod-2);
    for(i=maxn-1;i>=0;i--) p[i]=p[i+1]*(i+1)%mod;
}
ll cal(ll n,ll m){
    ll zc,i,j,k;
    if(m<0 or m>n) return 0;
    return s[n]*p[m]%mod*p[n-m]%mod;
}
int main(){
    ll n,m,t,ans,i,j,k;
    init();
    scanf("%lld",&t);
    while(t--){
        scanf("%lld%lld",&n,&m);
        ans=cal(n,m);
        printf("%lld\n",ans);
    }
    return 0;
}