新疆-Coconut(水)

#include <bits/stdc++.h>using namespace std;typedef long long ll;typedef pair<int,int> ii;const int N=2e5+20,inf=0x3f3f3f3f;int c[N],d[N];int main(){int T;cin>>T;while(T--){int n,b;cin>>n>>b;for(int i=1;i<=n;i++)scanf("%d",&c[i]);for(int i=2;i<=n;i++)scanf("%d",&d[i]);int res=0;bool flag=true;res+=c[1];for(int i=2;i<=n;i++){if(res<d[i]*b){flag=false;break;}elseres-=d[i]*b,res+=c[i];}if(flag)puts("Yes");elseputs("No");}return 0;}