1

AC

#include <iostream>
#include <cstdio>
using namespace std;

double ans,S,H,p,T,V,n,l;
int main()
{
	cin>>T;
	while(T--)
	{
		cin>>n;
		ans=0;
		for(int i=1;i<=n;i++)
		{
			cin>>l>>p;
			if(p<1.0)
			ans+=p*l*l*l;
			else
			ans+=l*l*l;
		}
		cin>>S>>H>>V;
		ans+=V;
		if(ans/S<=H)
			printf("%.2f\n",ans/S);
		else 
			printf("%.2f\n",H);
	}
}

wa

#include <iostream>
#include <cstdio>
using namespace std;

double ans,S,H,p[1005],T,V,n,l[1005];
int main()
{
	cin>>T;
	while(T--)
	{
		cin>>n;
		for(int i=1;i<=n;i++)
		{
			cin>>l[i]>>p[i];
		}
		cin>>S>>H>>V;
		ans=V;
		for(int i=1;i<=n;i++)
		{
			if(p[i]<1.0)
			ans+=p[i]*l[i]*l[i]*l[i];
			else
			ans+=l[i]*l[i]*l[i];
		}
		if(ans/S<=H)
			printf("%.2f\n",ans/S);
		else 
			printf("%.2f\n",H);
	}
}