#include
     
      #include
      
       using namespace std;struct node{	double num;	double price;	double weight;};int cmp(const void *a, const void *b){	node aa = *(node*)a;	node bb = *(node*)b;	if (aa.price / aa.num > bb.price / bb.num) return -1;	else if (aa.price / aa.num < bb.price / bb.num) return 1;	else return 0;}int main(){	int a, b, cnt = 0;	double temp = 0;	cin >> a >> b;	node mooncake[a];	for (int i = 0; i < a; i++)cin >> mooncake[i].num;	for (int i = 0; i < a; i++)cin >> mooncake[i].price;	for (int i = 0; i < a; i++)mooncake[i].weight = 1.0 * mooncake[i].price / mooncake[i].num;	qsort(mooncake, a, sizeof(mooncake[0]), cmp);	while (b != 0 && cnt != a){		if (b >= mooncake[cnt].num) {			temp += mooncake[cnt].price;			b -= mooncake[cnt].num;			cnt++;		}		else{			temp += b * mooncake[cnt++].weight;			b = 0;		}	}	printf("%.2f", temp);	return 0;}