#include <iostream>
#include <cstdio>
using namespace std;
const int N=1e4+4;
typedef long long ll;
ll jc[N],inv[N];
ll n,p;
ll ksm(ll x,ll y){
    ll res=1;
    while(y){
        if(y&1){
            res=(res*x)%p;
        }
        x=(x*x)%p;
        y>>=1;
    }
    return res;
}
ll a[N],b[N];
ll C(ll x,ll y){
    if(y>x) return 0;
    return jc[x]*inv[y]%p*inv[x-y]%p;
}
int main(){
    freopen("BBQ.in","r",stdin);
    freopen("BBQ.out","w",stdout);
    cin>>n>>p;
    jc[0]=1;
    for(int i=1;i<=N-4;i++){
        jc[i]=(jc[i-1]*i)%p;
        inv[i]=ksm(jc[i],p-2);
    }
    for(int i=1;i<=n;i++){
        cin>>a[i]>>b[i];
    }
    ll ans=0;
    for(int i=1;i<=n;i++){
        for(int j=i+1;j<=n;j++){
            ans+=C(a[i]+a[j]+b[i]+b[j],a[i]+a[j]);
            ans%=p;
        } 
    }
    cout<<ans;
    return 0;
}