#include<bits/stdc++.h>
using namespace std;
const int maxn=1e4+3;
int n,k,c[maxn],w[maxn];
int ans=0,sum=0,ct=0;
signed main()
{
	//freopen("road.in","r",stdin);
	//freopen("road.out","w",stdout);
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>k;
	for(int i=1;i<=n-1;i++) 
	{
		cin>>c[i];
		sum+=c[i];	
	}
	for(int i=1;i<=n;i++) cin>>w[i];
	int km=0;
	for(int i=1;i<=n-1;i++) //第五个站点不用加油 
	{
		if(km<c[i]) //加油
		{
			if(c[i]%k==0)
				km+=(c[i]/k);
			else
				km+=((c[i]/k)+1);
			ans+=w[i]*km;
			km*=k;
			cout<<km<<" "<<ans<<" "<<i<<endl;
		}
		km-=c[i];
	}
	cout<<ans<<endl;
	return 0;
}