#include <bits/stdc++.h>
#define int long long
using namespace std;
int n,m;
int  gcd(int a,int b){
	if(a%b==0) return b;
	else return gcd(b,a%b);	
}
int lcm(int a,int b){
	return a*b/gcd(a,b);
}
int fenzi[105],fenmu[105],zhengshu[105];
signed main(){
	freopen("fenshu.in","r",stdin);
	freopen("fenshu.out","w",stdout);
	int sum;
	cin>>n>>m; 
	for(int i=1;i<=n;i++){
		int p,q;
		cin>>p>>q;
		fenzi[i]=p; fenmu[i]=q;
	}
	for(int i=1;i<=n-1;i++){
		int k=lcm(fenmu[i],fenmu[i+1]);
		int xx=k/fenmu[i],yy=k/fenmu[i+1];
		fenzi[i+1]=yy*fenzi[i]+xx*fenzi[i+1];
		fenmu[i+1]=k;
		int w=gcd(fenzi[i+1],fenmu[i+1]);
	    fenzi[i+1]=fenzi[i+1]/w; fenmu[i+1]=fenmu[i+1]/w;
	}
	for(int i=1;i<=m;i++){
		int k;
		cin>>k;
		zhengshu[i]=k;
	} 
	for(int i=1;i<=m;i++){
		fenmu[n]*=zhengshu[i];
	}
	if(fenzi[n]%fenmu[n]==0) cout<<fenzi[n]/fenmu[n];
	else{
		int w=gcd(fenzi[n],fenmu[n]);
	    fenzi[n]=fenzi[n]/w; fenmu[n]=fenmu[n]/w;
	    cout<<fenzi[n]<<" "<<fenmu[n];
	}
	
	return 0;
}